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HILOSOPHICAL CLASSICS 




Religion o^§igug^X,ibrary No. 45 

m 

An Enquiry 

Concerning Human 

Understanding 

AND SELECTIONS FROM 
A TREATISE OF HUMAN NATURE 

BY 

DAVID HUME 



CHICAGO 
THE OPEN COURT PUBLISHING COMPANY 

Monograph 



AN ENQUIRY 

CONCERNING 

HUMAN UNDERSTANDING 

AND SELECTIONS FROM 

A TREA TISE OF HUMAN NA TURE 



BY 
DAVID HUME 



WITH HUME'S AUTOBIOGRAPHY AND 
A LETTER FROM ADAM SMITH 



CHICAGO 

THE OPEN COURT PUBLISHING CO. 

4921 



6< 



PRINTED IN THE UNITED STATES OP AMERICA 






PUBLISHERS' PREFACE. 

THE present volume is the second of the series of Phil- 
osophical Classics which The Open Court Publishing 
Company purposes issuing in cheap form for the convenience 
and instruction of the general reading public. It is an un- 
annotated reprint, merely, of the Enquiry Concerning Human 
Understanding, made from the posthumous edition of 1777, 
together with Hume's charming autobiography and the 
eulogistic letter of Adam Smith, usually prefixed to the 
History of England. These additions, with the portrait by 
Ramsay, which forms the frontispiece to the volume, render 
the picture of Hume's life complete, and leave but a word to 
be said concerning his philosophical importance. 

With the great public, Hume's fame has always rested 
upon his History of England, — a work now antiquated as his- 
tory and remarkable only for the signal elegance and sym- 
metry of its style. But this once prevalent opinion, our age 
has reversed, and, as has been well remarked,* "Hume, the 
spiritual father of Kant, now takes precedence over Hume, the 
rival of Robertson and Gibbon." It is precisely here, in fact, 
that Hume's significance for the history of thought lies. With 
him modern philosophy entered upon its Kantian phase, be- 
came critical and positivistic, became a theory of knowledge. 
For the old "false and adulterate" metaphysics he sought to 
substitute a "true" metaphysics, based on the firm founda- 
tions of reason and experience. His scepticism, — and of 
scepticism he has since been made the standard-bearer, — was 
directed against the old ontology only, and not against science 
proper (inclusive of philosophy). "Had Hume been an 
absolute sceptic he could never have produced an Immanuel 
Kant. . . . The spirit of the theoretical philosophy of Hume 
and Kant, the fundamental conception of their investigations, 
and the goal at which they aim, are perfectly identical. Theirs 

•Alfred Weber, History of Philosophy, New York, 1896. 



? 



PUBLISHERS' PREFACE. 

is the critical spirit, and positive knowledge the goal at which 
they aim. To claim for Kant the sole honor of having 
founded criticism is an error which a closer study of British 
philosophy tends to refute."! 

To this reprint of Hume's Enquiry Concerning Human 
Understanding has been added a supplement containing se- 
lections from his earlier and longer philosophical work, the 
Treatise on Human Understanding, referred to in the 
"Author's Advertisement" to the Enquiry (page xxviii., 
this edition). In spite of Hume's deprecatory reference to 
the Treatise, it remains the completest expression of his 
philosophical doctrine. The selected portions of the 
Treatise comprise (i) certain sections on causality which 
amplify the causal doctrine of the Enquiry and may profit- 
ably be read after Section VII. of the latter work; and (2) 
those sections which embody the essential features of Hume's 
constructive philosophy, his conception of matter and of self 
of spirit. Nothing in the Enquiry, with the exception of a 
few paragraphs of Section XII., corresponds to these sections 
of the Treatise. They should be read before, or in place 
of, the comparatively irrelevant sections, IX-XL, of the 
Enquiry. 

The first part of this book, pages 1 to 174, has been edited 
by Mr. Thomas J. McCormack of La Salle, 111., now principal 
of the La Salle Township High School. The remainder, 
pages 175 to 263, has been edited by Prof. Mary Whiton 
Calkins, of Wellesley College, Wellesley, Mass. 

THE OPEN COURT PUBLISHING CO. 
March, 1907. 

t Weber, he. cit., pp. 419-420. 



THE LIFE OF DAVID HUME, ESQ. 



WRITTEN BY HIMSELF. 



MY OWN LIFE. 



TT is difficult for a man to speak long of himself 
*■ without vanity ; therefore I shall be short. It may 
be thought an instance of vanity that I pretend at all 
to write my life ; but this narrative shall contain little 
more than the history of my writings ; as, indeed, al 
most all my life has been spent in literary pursuits 
and occupations. The first success of most of my 
writings was not such as to be an object of vanity. 

I was born the twenty-sixth of April, 171 1, old 
style, at Edinburgh. I was of a good family, both 
by father and mother : my father's family is a branch 
of the earl of Home's, or Hume's ; and my ancestors 
had been proprietors of the estate which my brother 
possesses, for several generations. My mother was 
daughter of Sir David Falconer, president of the col- 
lege of justice ; the title of Lord Halkerton came by 
succession to her brother. 

My family, however, was not rich ; and being my- 
self a younger brother, my patrimony, according to 
the mode of my country, was of course very slender. 



vi AUTOBIOGRAPHY, 

My father, who passed for a man of parts, died when 
I was an infant, leaving me, with an elder brother and 
a sister, under the care of our mother, a woman of 
singular merit, who, though young and handsome, 
devoted herself entirely to the rearing and educating 
of her children. I passed through the ordinary course 
of education with success, and was seized very early 
with a passion for literature, which has been the ru- 
ling passion of my life, and the great source of my en- 
joyments. My studious disposition, my sobriety, and 
my industry, gave my family a notion that the law 
was a proper profession for me; but I found an insur- 
mountable aversion to every thing but the pursuits of 
philosophy and general learning; and while they 
fancied I was poring upon Voet and Vinnius, Cicero 
and Virgil were the authors which I was secretly 
devouring. 

My very slender fortune, however, being unsuitable 
to this plan of life, and my health being a little broken 
by my ardent application, I was tempted, or rather 
forced, to make a very feeble trial for entering into a 
more active scene of life. In 1734, I went to Bristol, 
with some recommendations to several eminent mer- 
chants ; but in a few months found that scene totally 
unsuitable to me. I went over to France, with a view 
of prosecuting my studies in a country retreat ; and I 
there laid that plan of life which I have steadily and 
successfully pursued. I resoived to make a very rigid 
frugality supply my deficiency of fortune, to maintain 



AUTOBIOGRAPHY. vii 

unimpaired my independency, and to regard every 
object as contemptible, except the improvements of 
my talents in literature. 

During my retreat in France, first at Rheims, but 
chiefly at La Fleche, in Anjou, I composed my Trea- 
tise of Human Nature. After passing three years very 
agreeably in that country, I came over to London in 
1737. In the end of 1738, I published my Treatise, 
and immediately went down to my mother and my 
brother, who lived at his country house, and was 
employing himself very judiciously and successfully 
in the improvement of his fortune. 

Never literary attempt was more unfortunate than 
my Treatise of Human Nature. It fell dead-born 
from the press, without reaching such distinction as 
even to excite a murmur among the zealots. But be- 
ing naturally of a cheerful and sanguine temper, I very 
soon recovered the blow, and prosecuted with great 
ardor my studies in the country. In 1742, I printed 
at Edinburgh the first part of my Essays. The work 
was favorably received, and soon made me entirely 
forget my former disappointment. I continued with 
my mother and brother in the country, and in that 
time recovered the knowledge of the Greek language, 
which I had too much neglected in my early youth. 

In 1745, I received a letter from the marquis of 
Annandale, inviting me to come and live with him in 
England ; I found also that the friends and family of 
that young nobleman were desirous of putting him 



viii AUTOBIOGRAPHY. 

under my care and direction, for the state of his mind 
and health required it. I lived with him a twelve- 
month. My appointments during that time made a 
considerable accession to my small forture. I then 
received an invitation from General St. Clair to attend 
him as a secretary to his expedition, which was at first 
meant against Canada, but ended in an incursion on 
the coast of France. Next year, to wit, 1747, I re- 
ceived an invitation from the general to attend him in 
the same station in his military embassy to the courts 
of Vienna and Turin. I then wore the uniform of an 
officer, and was introduced at these courts as aid-de- 
camp to the general, along with Sir Harry Erskine and 
Captain Grant, now General Grant. These two years 
were almost the only interruptions which my studies 
have received during the course of my life : I passed 
them agreeably, and in good company; and my ap- 
pointments, with my frugality, had made me reach a 
fortune which I called independent, though most of 
my friends were inclined to smile when I said so : in 
short, I was now master of near a thousand pounds. 

I had always entertained a notion, that my want 
of success in publishing the Treatise of Human Na- 
ture had proceeded more from the manner than the 
matter, and that I had been guilty of a very usual 
indiscretion, in going to the press too early. I, there- 
fore, cast the first part of that work anew in the In- 
quiry concerning Human Understanding, which was 
published while I was at Turin. But this piece was 



A UTOBIO GRAPHY. ix 

at first little more successful than the Treatise on 
Human Nature. On my return from Italy, I had 
the mortification to find all England in a ferment, on 
account of Dr. Middleton's Free Inquiry, while my 
performance was entirely overlooked and neglected. 
A new edition, which had been published at London, 
of my Essays, moral and political, met not with a 
much better reception. 

Such is the force of natural temper, that these dis- 
appointments made little or no impression on me. I 
went down, in 1749, and lived two years with my 
brother at his country house, for my mother was now 
dead. I there composed the second part of my Essay, 
which I called Political Discourses, and also my In- 
quiry concerning the Principles of Morals, which is 
another part of my Treatise that I cast anew. Mean- 
while, my bookseller, A. Millar, informed me, that my 
former publications (all but the unfortunate Treatise) 
were beginning to be the subject of conversation; 
that the sale of them was gradually increasing, and 
that new editions were demanded. Answers by rev- 
erends and right reverends came out two or three in 
a year ; and I found, by Dr. Warburton's railing, that 
the books were beginning to be esteemed in good 
company. However, I had fixed a resolution, which 
1 inflexibly maintained, never to reply to any body; 
and not being very irascible in my temper, I have 
easily kept myself clear of all literary squabbles. These 
symptoms of a rising reputation gave me encourage- 



x A UTOBIO GRAPH Y. 

merit, as I was ever more disposed to see the favorable 
than unfavorable side of things; a turn of mind which 
it is more happy to possess, than to be born to an 
estate of ten thousand a year. 

In 1 75 1, I removed from the country to the town, 
the true scene for a man of letters. In 1752 were 
published at Edinburgh, where I then lived, my Politi- 
cal Discourses, the only work of mine that was suc- 
cessful on the first publication. It was well received 
at home and abroad. In the same year was published, 
at London, my Inquiry concerning the Principles of 
Morals ; which, in my own opinion, (who ought not 
to judge on that subject,) is, of all my writings, his- 
torical, philosophical, or literary, incomparably the 
best. It came unnoticed and unobserved into the 
world. 

In 1752, the Faculty of Advocates chose me their 
librarian, an office from which I received little or no 
emolument, but which gave me the command of a 
large library. I then formed the plan of writing the 
History of England ; but being frightened with the 
notion of continuing a narrative through a period of 
seventeen hundred years, I commenced with the acces- 
sion of the house of Stuart, an epoch when, I thought, 
the misrepresentations of faction began chiefly to take 
place. I was, I own, sanguine in my expectations of 
the success of this work. I thought that I was the 
only historian that had at once neglected present 
power, interest and authority, and the cry of popular 



AUTOBIOGRAPHY. xi 

prejudices ; and as the subject was suited to every 
capacity, I expected proportional applause. But mis- 
erable was my disappointment ; I was assailed by one 
cry of reproach, disapprobation, and even detestation; 
English, Scotch, and Irish, whig and tory, churchman 
and sectary, freethinker and religionist, patriot and 
courtier, united in their rage against the man who 
had presumed to shed a generous tear for the fate of 
Charles I. and the earl of Strafford; and after the 
first ebullitions of their fury were over, what was still 
more mortifying, the book seemed to sink into obliv- 
ion. Mr. Millar told me that in a twelvemonth he 
sold only forty-five copies of it. I scarcely, indeed, 
heard of one man in the three kingdoms, considerable 
for rank or letters, that could endure the book. I 
must only except the primate of England, Dr. Her- 
ring, and the primate of Ireland, Dr. Stone, which 
seem two odd exceptions. These dignified prelates 
separately sent me messages not to be discouraged. 

I was, however, I confess, discouraged ; and had 
not the war been at that time breaking out between 
France and England, I had certainly retired to some 
provincial town of the former kingdom, have changed 
my name, and never more have returned to my native 
country. But as this scheme was not now practica- 
ble, and the subsequent volume was considerably 
advanced, I resolved to pick up courage and to per- 
severe. 

In this interval, I published, at London, my Natu- 



xii A UTOBIO GRAPHY, 

ral History of Religion, along with some other small 
pieces. Its public entry was rather obscure, except 
only that Dr. Hurd wrote a pamphlet against it, with 
all the illiberal petulance, arrogance, and scurrility, 
which distinguish the Warburtonian school. This 
pamphlet gave me some consolation for the other- 
wise indifferent reception of my performance. 

In 1756, two years after the fall of the first volume, 
was published the second volume of my history, con- 
taining the period from the death of Charles I. till the 
revolution. This performance happened to give less 
displeasure to the whigs, and was better received. 
It not only rose itself, but helped to buoy up its un- 
fortunate brother. 

But though I had been taught by experience that 
the whig party were in possession of bestowing all 
places, both in the state and in literature, I was so 
little inclined to yield to their senseless clamor, that 
in above a hundred alterations, which further study, 
reading, or reflection engaged me to make in the 
reigns of the two first Stuarts, I have made all of 
them invariably to the tory side. It is ridiculous to 
consider the English constitution before that period 
as a regular plan of liberty. 

In 1759, I published my history of the house of 
Tudor. The clamor against this performance was 
almost equal to that against the history of the two 
first Stuarts. The reign of Elizabeth was particularly 
obnoxious. But I was now callous against the im 



AUTOBIOGRAPHY. xitt 

pressions of public folly, and continued very peaceably 
and contentedly, in my retreat at Edinburgh, to finish, 
in two volumes, the more early part of the English 
history, which I gave to the public in 1761, with 
tolerable, and but tolerable, success. 

But, notwithstanding this variety of winds and 
seasons, to which my writings had been exposed, they 
had still been making such advances, that the copy- 
money given me by the booksellers much exceeded any 
thing formerly known in England ; I was become not 
only independent, but opulent. I retired to my native 
country of Scotland, determined never more to set my 
foot out of it ; and retaining the satisfaction of never 
having preferred a request to one great man, or even 
making advances of friendship to any of them. As I 
was now turned of fifty, I thought of passing all the 
rest of my life in this philosophical manner : when I 
received, in 1763, an invitation from the earl of Hert- 
ford, with whom I was not in the least acquainted, to 
attend him on his embassy to Paris, with a near pros- 
pect of being appointed secretary to the embassy; and, 
in the mean while, of performing the functions of that 
office. This offer, however inviting, I at first declined; 
both because I was reluctant to begin connections 
with the great, and because I was afraid that the 
civilities and gay company of Paris would prove dis- 
agreeable to a person of my age and humor ; but on 
his lordship's repeating the invitation, I accepted of it. 
I have every reason, both of pleasure and interest, to 



xiv AUTOBIOGRAPHY, 

think myself happy in my connexions with that noble- 
man, as well as afterwards with his brother, General 
Conway. 

Those who have not seen the strange effects of 
modes, will never imagine the reception I met with at 
Paris, from men and women of all ranks and stations. 
The more I resiled from their excessive civilities, the 
more I was loaded with them. There is, however, 
a real satisfaction in living at Paris, from the great 
number of sensible, knowing, and polite company 
with which that city abounds above all places in the 
universe. I thought once of settling there for life. 

I was appointed secretary to the embassy ; and, in 
summer, 1765, Lord Hertford left me, being appointed 
lord lieutenant of Ireland. I was charge" d'affaires till 
the arrival of the duke of Richmond, towards the end 
of the year. In the beginning of 1766, I left Paris, 
and next summer went to Edinburgh, with the same 
view as formerly, of burying myself in a philosophical 
retreat. I returned to that place, not richer, but with 
much more money, and a much larger income, by 
means of Lord Hertford's friendship, than I left it; 
and I was desirous of trying what superfluity could 
produce, as I had formerly made an experiment of a 
competency. But in 1767, I received from Mr. Con- 
way an invitation to be under-secretary ; and this 
invitation, both the character of the person, and mv 
connexions with Lord Hertford, prevented me from 
declining. I returned to Edinburgh in 1769, very 



A UTOBIO GRAPHY, xv 

opulent, (for I possessed a revenue of one thousand 
pounds a year,) healthy, and though somewhat stricken 
in years, with the prospect of enjoying long my ease 5 
and of seeing the increase of my reputation. 

In spring, 1775, I was struck with a disorder in 
my bowels, which at first gave me no alarm, but has 
since, as I apprehend it, become mortal and incurable. 
I now reckon upon a speedy dissolution. I have suf- 
fered very little pain from my disorder; and what is 
more strange, have, notwithstanding the great decline 
of my person, never suffered a moment's abatement 
of my spirits; insomuch, that were I to name a period 
of my life which I should most choose to pass over 
again, I might be tempted to point to this later period. 
I possess the same ardor as ever in study, and the same 
gayety in company. I consider, besides, that a man 
of sixty-five, by dying, cuts off only a few years of 
infirmities ; and though I see many symptoms of my 
literary reputation's breaking out at last with addi- 
tional lustre, I know that I could have but few years 
to enjoy it. It is difficult to be more detached from 
life than I am at present. 

To conclude historically with my own character: 
I am, or rather was, (for that is the style I must now 
use in speaking of myself, which emboldens me the 
more to speak my sentiments;) I was, I say, a man of 
mild disposition, of command of temper, of an open 
social, and cheerful humor, capable of attachment, but 
little susceptible of enmity, and of great moderation 



*vi A UTOBIO GRAPHY. 

in all my passions. Even my love of literary fame, 
my ruling passion, never soured my temper, notwith- 
standing my frequent disappointments. My company 
was not unacceptable to the young and careless, as 
well as to the studious and literar) T ; and as I took a 
particular pleasure in the company of modest women, 
I had no reason to be displeased with the reception I 
met with from them. In a word, though most men, 
anywise eminent, have found reason to complain of 
Calumny, I never was touched, or even attacked, by 
her baleful tooth ; and though I wantonly exposed 
myself to the rage of both civil and religious factions, 
they seemed to be disarmed in my behalf of their 
wonted fury. My friends never had occasion to vin- 
dicate any one circumstance of my character and con- 
duct ; not but that the zealots, we may well suppose, 
would have been glad to invent and propagate any 
story to my disadvantage, but they could never find 
any which they thought would wear the face of prob- 
ability. I cannot say there is no vanity in making this 
funeral oration of myself, but I hope it is not a mis- 
placed one; and this is a matter of fact which is easily 
cleared and ascertained. 

April 18, 1776. 



LETTER FROM ADAM SMITH, LL. D. 

TO WILLIAM STRAHAN, ESQ. 

KlRKALDY, FlFESHIRE, Nov. 9, 1776. 

Dear Sir, 

IT is with a real, though a very melancholy pleasure, 
that I sit down to give you some account of the 
behaviour of our late excellent friend, Mr. Hume, 
during his last illness. 

Though, in his own judgement, his disease was 
mortal and incurable, yet he allowed himself to be 
prevailed upon, by the entreaty of his friends, to try 
what might be the effects of a long journey. A few 
days before he set out, he wrote that account of his 
own life, which, together with his other papers, he 
has left to your care. My account, therefore, shall 
begin where his ends. 

He set out for London towards the end of April, 
and at Morpeth met with Mr. John Home and myself, 
who had both come down from London on purpose to 
see him, expecting to have found him at Edinburgh. 
Mr. Home returned with him, and attended him dur- 
ing the whole of his stay in England, with that care 
and attention which might be expected from a temper 



xviii LETTER FROM ADAM SMITH. 

so perfectly friendly and affectionate As I had written 
to my mother that she might expect me in Scotland, 
I was under the necessity of continuing my journey. 
His disease seemed to yield to exercise and change of 
air; and when he arrived in London, he was apparently 
in much better health than when he left Edinburgh. 
He was advised to go to Bath to drink the waters, 
which appeared for some time to have so good an effect 
upon him, that even he himself began to entertain, 
what he was not apt to do, a better opinion of his own 
health. His symptoms, however, soon returned with 
their usual violence ; and from that moment he gave 
up all thoughts of recovery, but submitted with the 
utmost cheerfulness, and the most perfect compla- 
cency and resignation. Upon his return to Edinburgh, 
though he found himself much weaker, yet his cheer- 
fulness never abated, and he continued to divert him- 
self, as usual, with correcting his own works for a new 
edition, with reading books of amusement, with the 
conversation of his friends ; and, sometimes in the 
evening, with a party at his favorite game of whist. 
His cheerfulness was so great, and his conversation 
and amusements ran so much in their usual strain, 
that, notwithstanding all bad symptoms, many people 
could not believe he was dying. "I shall tell your 
friend, Colonel Edmonstone,"said Dr. Dundas to him 
one day, "that I left you much better, and in a fair 
way of recovery." "Doctor," said he, "as I believe 
you would not choose to tell any thing but the truth, 



LETTER FROM ADAM SMITH. xix 

you had better tell him that I am dying as fast as my 
enemies, if I have any, could wish, and as easily and 
cheerfully as my best friends could desire." Colonel 
Edmonstone soon afterwards came to see him, and 
take leave of him ; and on his way home he could not 
forbear writing him a letter, bidding him once more 
an eternal adieu, and applying to him, as to a dying 
man, the beautiful French verses in which the Abbe" 
Chaulieu, in expectation of his own death, laments his 
approaching separation from his friend the Marquis 
de la Fare. Mr. Hume's magnanimity and firmness 
were such, that his most affectionate friends knew 
that they hazarded nothing in talking or writing to 
him as to a dying man, and that so far from being 
hurt by this frankness, he was rather pleased and flat- 
tered by it. I happened to come into his room while 
he was reading this letter, which he had just received, 
and which he immediately showed me. I told him, 
that though I was sensible how very much he was 
weakened, and that appearances were in many respects 
very bad, yet his cheerfulness was still so great, the 
spirit of life seemed still to be so very strong in him, 
that I could not help entertaining some faint hopes. 
He answered, "Your hopes are groundless. An ha- 
bitual diarrhoea of more than a year's standing, would 
be a very bad disease at any age; at my age it is a 
mortal one. When I lie down in the evening, I feel 
myself weaker than when I rose in the morning ; and 
when I rise in the morning, weaker than when I lay 



xx LETTER FROM ADAM SMITH. 

down in the evening. I am sensible, besides, that; 
some of my vital parts are affected, so that I must 
soon die." "Well," said I, "if it must be so, you 
have at least the satisfaction of leaving all your friends, 
your brother's family in particular, in great prosper- 
ity." He said that he felt that satisfaction so sensibly, 
that when he was reading, a few days before, Lucian's 
Dialogues of the Dead, among all the excuses which 
are alleged to Charon for not entering readily into his 
boat, he could not find one that fitted him : he had no 
house to finish, he had no daughter to provide for, he 
had no enemies upon whom he wished to revenge 
himself. "I could not well imagine," said he, "what 
excuse I could make to Charon in order to obtain a 
little delay. I have done every thing of consequence 
which I ever meant to do ; and I could at no time ex- 
pect to leave my relations and friends in a better sit- 
uation than that in which I am now likely to leave them: 
I, therefore, have all reason to die contented." He 
then diverted himself with inventing several jocular 
excuses, which he supposed he might make to Charon, 
and with imagining the very surly answers which it 
might suit the character of Charon to return to them. 
''Upon further consideration," said he, "I thought I 
might say to him, 'Good Charon, I have been correct- 
ing my works for a new edition. Allow me a little 
time, that I may see how the public receives the alter- 
ations.' But Charon would answer, 'When you have 
seen the effect of these, you will be for making other 



LETTER FROM ADAM SMITH. xxi 

alterations. There will be no end of such excuses; 
so, honest friend, please step into the boat.' But I 
might still urge, 'Have a little patience, good Charon: 
I have been endeavouring to open the eyes of the pub- 
lic. If I live a few years longer, I may have the satis- 
faction of seeing the downfall of some of the prevailing 
systems of superstition.' But Charon would then lose 
all temper and decency. ' You loitering rogue, that will 
not happen these many hundred years. Do you fancy 
I will grant you a lease for so long a term ? Get into 
the boat this instant, you lazy, loitering rogue.' " 

But, though Mr. Hume always talked of his ap- 
proaching dissolution with great cheerfulness, he never 
affected to make any parade of his magnanimity. He 
never mentioned the subject but when the conversa- 
tion naturally led to it, and never dwelt longer upon 
it than the course of the conversation happened to re- 
quire ; it was a subject indeed which occurred pretty 
frequently, in consequence of the inquiries which his 
friends, who came to see him, naturally made concern- 
ing the state of his health. The conversation which 
I mentioned above, and which passed on Thursday 
the eighth of August, was the last, except one, that I 
ever had with him. He had now become so very 
weak, that the company of his most intimate friends 
fatigued him ; for his cheerfulness was still so great, 
his complaisance and social disposition were still so 
entire, that when any friend was with him, he could 
not help talking more, and with greater exertion, than 



xxii LETTER FROM ADAM SMITH. 

suited the weakness of his body. At his own desire, 
therefore, I agreed to leave Edinburgh, where I was 
staying partly upon his account and returned to my 
mother's house here at Kirkaldy, upon condition that 
he would send for me whenever he wished to see me ; 
the physician who saw him most frequently, Dr. Black, 
undertaking, in the mean time, to write me occasion- 
ally an account of the state of his health. 

On the twenty-second of August, the doctor wrote 
me the following letter : — 

" Since my last, Mr. Hume has passed his time 
pretty easily, but is much weaker. He sits up, goes 
down stairs once a day, and amuses himself with 
reading, but seldom sees any body. He finds that 
even the conversation of his most intimate friends 
fatigues and oppresses him ; and it is happy that he 
does not need it, for he is quite free from anxiety, im- 
patience, or low spirits, and passes his time very well 
with the assistance of amusing books. " 

I received, the day after, a letter from Mr. Hume 
himself, of which the following is an extract : — 

" Edinburgh, 23d August, 1776. 

"My Dearest Friend, 

"I am obliged to make use of my nephew's hand 

in writing to you, as I do not rise to-day. 

* * 

"I go very fast to decline, and last night had a 

small fever, which I hoped might put a quicker period 



LETTER FROM ADAM SMITH. xxiii 

to this tedious illness ; but unluckily it has, in a great 
measure, gone off. I cannot submit to your coming 
over here on my account, as it is possible for me to 
see you so small a part of the day ; but Dr. Black can 
better inform you concerning the degree of strength 
which may from time to time remain with me. Adieu, 
etc." 

Three days after, I received the following letter 
from Dr. Black : — 

"Edinburgh, Monday, 26th August, 1776, 
"Dear Sir, 

"Yesterday, about four o'clock, afternoon, Mr, 
Hume expired. The near approach of his death be- 
came evident in the night between Thursday and Fri- 
day, when his disease became excessive, and soon 
weakened him so much, that he could no longer rise 
out of his bed. He continued to the last perfectly 
sensible, and free from much pain or feelings of dis- 
tress. He never dropped the smallest expression of 
impatience ; but when he had occasion to speak to 
the people about him, always did it with affection and 
tenderness. I thought it improper to write to bring 
you over, especially as I heard that he had dictated a 
letter to you, desiring you not to come. When he 
became very weak, it cost him an effort to speak; 
and he died in such a happy composure of mind, that 
nothing could exceed it." 



xxiv LETTER FROM ADAM SMITH. 

Thus died our most excellent and never to be for- 
gotten friend \ concerning whose philosophical opin- 
ions men will, no doubt, judge variously, every one 
approving or condemning them, according as they 
happen to coincide or disagree with his own, but con- 
cerning whose character and conduct there can scarce 
be a difference of opinion. His temper, indeed, 
seemed to be more happily balanced, if I may be al- 
lowed such an expression, than that perhaps of any 
other man I have ever known. Even in the lowest 
state of his fortune, his great and necessary frugality 
never hindered him from exercising, upon proper oc- 
casions, acts both of charity and generosity. It was 
a frugality founded not upon avarice, but upon the 
love of independency. The extreme gentleness of his 
nature never weakened either the firmness of his mind 
or the steadiness of his resolutions. His constant 
pleasantry was the genuine effusion of good nature and 
good humour, tempered with delicacy and modesty, 
and without even the slightest tincture of malignity, 
so frequently the disagreeable source of what is called 
wit in other men. It never was the meaning of his 
raillery to mortify ; and therefore, far from offending, 
it seldom failed to please and delight, even those who 
were frequently the objects of it ; there was not per- 
haps any one of all his great and amiable qualities 
which contributed more to endear his conversation. 
And that gayety of temper, so agreeable in society, 
but which is so often accompanied with frivolous and 



LETTER FROM ADAM SMITH. xxv 

superficial qualities, was in him certainly attended 
with the most severe application, the mosi extensive 
learning, the greatest depth of thought, and a capacity 
in every respect the most comprehensive. Upon the 
whole, I have always considered him, both in his life- 
time and since his death, as approaching as nearly to 
the idea of a perfectly wise and virtuous man as per- 
haps the nature of human frailty will permit. 

I ever am, dear sir, 

Most affectionally yours, 

Adam Smith, 



CONTENTS. 

PAGE 

Publishers' Preface iii 

Autobiography v 

Letter from Adam Smith to William Strahan .... xvii 

Author's Advertisement xxviii 

An Enquiry Concerning Human Understanding — 

Of the Different Species of Philosophy 1 

Of the Origin of Ideas 14 

Of the Association of Ideas 21 

Sceptical Doubts Concerning the Operations of the 

Understanding 23 

Sceptical Solution of these Doubts 40 

Of Probability 5T 

Of the Idea of Necessary Connexion 61 

Of Liberty and Necessity 82 

Of the Reason of Animals 109 

Of Miracles 114 

Of a Particular Providence and of a Future State . . 139 

Of the Academical or Sceptical Philosophy .... 158 
Selections from A Treatise of Human Nature — 
The Doctrine of Causality,, 
Book I. Part III. 

Section I. Of Knowledge 185 

Section II. Of Probability; and of the Idea of Cause 

and Effect 190 

Section III. Why a Cause Is Always Necessary . . 197 

Section XIV. Of the Idea of Necessary Connexion . . 202 
The Doctrine of Substance. 
Book I. Part I. 

Section VI. Of Modes and Substances 227 

Book I. Part II. 
Section VI. Of the Idea of Existence and of External 

Existence 229 

Book I. Part IV. 

Section II. Of Scepticism with regard to the Senses 232 

Section VI. Of Personal Identity 245 

Apfenpix , , * « . * 2,6X) 



AUTHOR'S ADVERTISEMENT. 

Most of the principles, and reasonings, contained in this vol- 
ume, 1 were published in a work in three volumes, called A Trea- 
tise of Human Nature: A work which the Author had projected 
before he left College, and which he wrote and published not long 
after. But not finding it successful, he was sensible of his error 
in going to the press too early, and he cast the whole anew in the 
following pieces, where some negligences in his former reasoning 
and more in the expression, are, he hopes, corrected. Yet several 
writers who have honoured the Author's Philosophy with answers, 
have taken care to direct all their batteries against that juvenile 
work, which the author never acknowledged, and have affected to 
triumph in any advantages, which, they imagined, they had ob- 
tained over it : A practice very contrary to all rules of candour 
and fair-dealing, and a strong instance of those polemical artifices 
which a bigotted zeal thinks itself authorized to employ. Hence- 
forth, the Author desires, that the following Pieces may alone be 
regarded as containing his philosophical sentiments and principles 

lVolume II. of the posthumous edition of Hume's works published in 
1777 and containing, besides the present Enquiry, A Dissertation on the Pas 
sions, and An Enquiry Concerning the Principles of Morals. A reprint of the 
latter treatise has already appeared in the Religion of Science Library (No. 
46), published by The Open Court Publishing Co.— Editor. 



SECTION I. 

OF THE DIFFERENT SPECIES OF PHILOSOPHY 

MORAL philosophy, or the science of human na- 
ture, may be treated after two different manners ; 
each of which has its peculiar merit, and may contrib- 
ute to the entertainment, instruction, and reformation 
of mankind. The one considers man chiefly as born 
for action ; and as influenced in his measures by taste 
and sentiment; pursuing one object, and avoiding 
another, according to the value which these objects 
seem to possess, and according to the light in which 
they present themselves. As virtue, of all objects, is 
allowed to be the most valuable, this species of philos- 
ophers paint her in the most amiable colours; borrow- 
ing all helps from poetry and eloquence, and treating 
their subject in an easy and obvious manner, and such 
as is best fitted to please the imagination, and engage 
the affections. They select the most striking observa- 
tions and instances from common life ; place opposite 
characters in a proper contrast ; and alluring us into 
the paths of virtue by the views of glory and happi- 
ness, direct our steps in these paths by the soundest 
precepts and most illustrious examples. They make 
\is feel the difference between vice and virtue ; they 
excite and regulate our sentiments ; and so they can 
but bend our hearts to the love of probity and true 
honour, they think, that they have fully attained the 
end of all their labours. 



a AN ENQUIRY CONCERNING 

The other species of philosophers consider man in 
the light of a reasonable rather than an active being, 
and endeavour to form his understanding more than 
cultivate his manners. They regard human nature as 
a subject of speculation ; and with a narrow scrutiny 
examine it, in order to find those principles, which 
regulate our understanding, excite our sentiments, and 
make us to approve or blame any particular object, 
action, or behaviour. They think it! a reproach to all 
literature, that philosophy should not yet have fixed, 
beyond controversy, the foundation of morals, reason- 
ing, and criticism ; and should for ever talk of truth 
and falsehood, vice and virtue, beauty and deformity, 
without being able to determine the source of these 
distinctions. While they attempt this arduous task, 
they are deterred by no difficulties ; but proceeding 
from particular instances to general principles, they 
still push on their enquiries to principles more gen- 
eral, and rest not satisfied till they arrive at those or- 
iginal principles, by which, in every science, all human 
curiosity must be bounded. Though their speculations 
seem abstract, and even unintelligible to common read- 
ers, they aim at the approbation of the learned and the 
wise; and think themselves sufficiently compensated 
for the labour of their whole lives, if they can discover 
some hidden truths, which may contribute to the in- 
struction of posterity. 

It is certain that the easy and obvious philosophy 
will always, with the generality of mankind, have the 
preference above the accurate and abstruse ; and by 
many will be recommended, not only as more agree- 
able, but more useful than the other. It enters more 
into common life; moulds the heart and affections; 
and, by touching those principles which actuate men, 



HUMAN UNDERSTANDING. 3 

reforms their conduct, and brings them nearer to that 
model of perfection which it describes. On the con- 
trary, the abstruse philosophy, being founded on a 
turn of mind, which cannot enter into business and 
action, vanishes when the philosopher leaves the shade, 
and comes into open day ; nor can its principles easily 
retain any influence over our conduct and behaviour. 
The feelings of our heart, the agitation of our passions, 
the vehemence of our affections, dissipate all its con- 
clusions, and reduce the profound philosopher to a 
mere plebeian. 

This also must be confessed, that the most dur- 
able, as well as justest fame, has been acquired by the 
easy philosophy, and that abstract reasoners seem 
hitherto to have enjoyed only a momentary reputation, 
from the caprice or ignorance of their own age, but 
have not been able to support their renown with more 
equitable posterity. It is easy for a profound philos- 
opher to commit a mistake in his subtile reasonings; 
and one mistake is the necessary parent of another, 
while he pushes on his consequences, and is not de- 
terred from embracing any conclusion, by its unusual 
appearance, or its contradiction to popular opinion. 
But a philosopher, who purposes only to represent the 
common sense of mankind in more beautiful and more 
engaging colours, if by accident he falls into error, 
goes no farther; but renewing his appeal to common 
sense, and the natural sentiments of the mind, returns 
into the right path, and secures himself from any dan- 
gerous illusions. The fame of Cicero flourishes at 
present ; but that of Aristotle is utterly decayed. La 
Bruyere passes the seas, and still maintains his repu- 
tation : But the glory of Malebranche is confined to 
his own nation, and to his own age. And Addison, 



4 AN ENQ UIR Y CONCERNING 

perhaps, will be read with pleasure, when Locke shall 
be entirely forgotten. 

The mere philosopher is a character, which is com- 
monly but little acceptable in the world, as being sup- 
posed to contribute nothing either to the advantage 
or pleasure of society ; while he lives remote from 
communication with mankind, and is wrapped up in 
principles and notions equally remote from their com- 
prehension. On the other hand, the mere ignorant is 
still more despised ; nor is any thing deemed a surer 
sign of an illiberal genius in an age and nation where 
the sciences flourish, than to be entirely destitute of 
all relish for those noble entertainments. The most 
perfect character is supposed to lie between those ex- 
tremes ; retaining an equal ability and taste for books, 
company, and business ; preserving in conversation 
that discernment and delicacy which arise from polite 
letters; and in business, that probity and accuracy 
which are the natural result of a just philosophy. In 
order to diffuse and cultivate so accomplished a char- 
acter, nothing can be more useful than compositions 
of the easy style and manner, which draw not too 
much from life, require no deep application or retreat 
to be comprehended, and send back the student among 
mankind full of noble sentiments and wise precepts, 
applicable to every exigence of human life. By means 
of such compositions, virtue becomes amiable, science 
agreeable, company instructive, and retirement enter- 
taining. 

Man is a reasonable being ; and as such, receives 
from science his proper food and nourishment : But 
so narrow are the bounds of human understanding, 
that little satisfaction can be hoped for in this partic- 
ular, either from the extent or security of his acquisi- 



HUMAN UNDERSTANDING. 5 

tions. Man is a sociable, no less than a reasonable 
being : But neither can he always enjoy company 
agreeable and amusing, or preserve the proper relish 
for them. Man is also an active being ; and from 
that disposition, as well as from the various necessities 
of human life, must submit to business and occupa- 
tion : But the mind requires some relaxation, and can- 
not always support its bent to care and industry. It 
seems, then, that nature has pointed out a mixed kind 
of life as most suitable to the human race, and secretly 
admonished them to allow none of these biasses to 
draw too much, so as to incapacitate them for other 
occupations and entertainments. Indulge your passion 
for science, says she, but let your science be human, 
and such as may have a direct reference to action and 
society. Abstruse thought and profound researches I 
prohibit, and will severely punish, by the pensive mel- 
ancholy which they introduce, by the endless uncer- 
tainty in which they involve you, and by the cold re- 
ception which your pretended discoveries shall meet 
with, when communicated. Be a philosopher; but, 
amidst all your philosophy, be still a man. 

Were the generality of mankind contented to pre- 
fer the easy philosophy to the abstract and profound, 
without throwing any blame or contempt on the latter, 
it might not be improper, perhaps, to comply with this 
general opinion, and allow every man to enjoy, with- 
out opposition, his own taste and sentiment. But as 
the matter is often carried farther, even to the absolute 
rejecting of all profound reasonings, or what is com- 
monly called metaphysics, we shall now proceed to con- 
sider what can reasonably be pleaded in their behalf. 

We may begin with observing, that one consider- 
able advantage, which results from the accurate and 



kNQum 



6 Ati kNQUFRY CONCEktflttS 

abstract philosophy, is, its subserviency to the easy 
and humane, which, without the former, can never 
attain a sufficient degree of exactness in its sentiments, 
precepts, or reasonings. All polite letters are nothing 
but pictures of human life in various attitudes and 
situations; and inspire us with different sentiments, 
of praise or blame, admiration or ridicule, according 
to the qualities of the object, which they set before 
us. An artist must be better qualified to succeed in 
this undertaking, who, besides a delicate taste and a 
quick apprehension, possesses an accurate knowledge 
of the internal fabric, the operations of the under- 
standing, the workings of the passions, and the various 
species of sentiment which discriminate vice and vir- 
tue. How painful soever this inward search or en- 
quiry may appear, it becomes, in some measure, re- 
quisite to those, who would describe with success the 
obvious and outward appearances of life and manners. 
The anatomist presents to the eye the most hideous 
and disagreeable objects ; but his science is useful to 
the painter in delineating even a Venus or an Helen. 
While the latter employs all the richest colours of his 
art, and gives his figures the most graceful and en- 
gaging airs ; he must still carry his attention to the 
inward structure of the human body, the position of 
the muscles, the fabric of the bones, and the use and 
figure of every part or organ. Accuracy is, in every 
case, advantageous to beauty, and just reasoning to 
delicate sentiment. In vain would we exalt the one 
by depreciating the other. 

Besides, we may observe, in every art or profes- 
sion, even those which most concern life or action, 
that a spirit of accuracy, however acquired, carries all 
of them nearer their perfection, and renders them 



HUMAN UNDERSTANDING. 7 

more subservient to the interests of society. And 
though a philosopher may live remote from business, 
the genius of philosophy, if carefully cultivated by sev- 
eral, must gradually diffuse itself throughout the whole 
society, and bestow a similar correctness on every 
art and calling. The politician will acquire greater 
foresight and subtility, in the subdividing and balanc- 
ing of power ; the lawyer more method and finer prin- 
ciples in his reasonings ; and the general more regular- 
ity in his discipline, and more caution in his plans 
and operations. The stability of modern governments 
above the ancient, and the accuracy of modern philos- 
ophy, have improved, and probably will still improve, 
by similar gradations. 

Were there no advantage to be reaped from these 
studies, beyond the gratification of an innocent curios- 
ity, yet ought not even this to be despised ; as being 
one accession to those few safe and harmless pleasures, 
which are bestowed on the human race. The sweetest 
and most inoffensive path of life leads through the 
avenues of science and learning ; and whoever can 
either remove any obstructions in this way, or open 
up any new prospect, ought so far to be esteemed a 
benefactor to mankind. And though these researches 
may appear painful and fatiguing, it is with some 
minds as with some bodies, which being endowed with 
vigorous and florid health, require severe exercise, 
and reap a pleasure from what, to the generality of 
mankind, may seem burdensome and laborious. Ob- 
scurity, indeed, is painful to the mind as well as to the 
eye ; but to bring light from obscurity, by whatever 
labour, must needs be delightful and rejoicing. 

But this obscurity in the profound and abstract 
philosophy, is objected to, not only as painful and 



8 AN ENQ UIR Y CONCERNING 

fatiguing, but as the inevitable source of uncertainty 
and error. Here indeed lies the justest and most 
plausible objection against a considerable part of meta- 
physics, that they are not properly a science ; but arise 
either from the fruitless efforts of human vanity, which 
would penetrate into subjects utterly inaccessible to 
the understanding, or from the craft of popular super- 
stitions, which, being unable to defend themselves on 
fair ground, raise these intangling brambles to cover 
and protect their weakness. Chaced from the open 
country, these robbers fly into the forest, and lie in 
wait to break in upon every unguarded avenue of the 
mind, and overwhelm it with religious fears and pre- 
judices. The stoutest antagonist, if he remit his watch 
a moment, is oppressed. And many, through cow- 
ardice and folly, open the gates to the enemies, and 
willingly receive them with reverence and submission, 
as their legal sovereigns. 

But is this a sufficient reason, why philosophers 
should desist from such researches, and leave super- 
stition still in possession of her retreat? Is it not 
proper to draw an opposite conclusion, and perceive 
the necessity of carrying the war into the most secret 
recesses of the enemy? In vain do we hope, that men, 
from frequent disappointment, will at last abandon 
such airy sciences, and discover the proper province 
of human reason. For, besides, that many persons 
find too sensible an interest in perpetually recalling 
such topics ; besides this, I say, the motive of blind 
despair can never reasonably have place in the sci- 
ences ; since, however unsuccessful former attempts 
may have proved, there is still room to hope, that the 
industry, good fortune, or improved sagacity of suc- 
ceeding generations may reach discoveries unknown 



HUMAN UNDERSTANDING. 9 

to former ages. Each adventurous genius will leap at 
the arduous prize, and find himself stimulated, rather 
than discouraged, by the failures of his predecessors ; 
while he hopes that the glory of achieving so hard an 
adventure is reserved for him alone. The only method 
of freeing learning, at once, from these abstruse ques- 
tions, is to enquire seriously into the nature of human 
understanding, and show, from an exact analysis of 
its powers and capacity, that it is by no means fitted 
for such remote and abstruse subjects. We must sub- 
mit to this fatigue, in order to live at ease ever after : 
And must cultivate true metaphysics with some care, 
in order to destroy the false and adulterate. Indo- 
lence, which, to some persons, affords a safeguard 
against this deceitful philosophy, is, with others, over- 
balanced by curiosity ; and despair, which, at some 
moments, prevails, may give place afterwards to san- 
guine hopes and expectations. Accurate and just rea- 
soning is the only catholic remedy, fitted for all per- 
sons and all dispositions ; and is alone able to subvert 
that abstruse philosophy and metaphysical jargon, 
which, being mixed up with popular superstition, ren- 
ders it in a manner impenetrable to careless reasoners, 
and gives it the air of science and wisdom. 

Besides this advantage of rejecting, after deliberate 
enquiry, the most uncertain and disagreeable part of 
learning, there are many positive advantages, which 
result from an accurate scrutiny into the powers and 
faculties of human nature. It is remarkable concern- 
ing the operations of the mind, that, though most in- 
timately present to us, yet, whenever they become the 
object of reflexion, they seem involved in obscurity ; 
nor can the eye readily find those lines and boundaries, 
w^iich discriminate and distinguish them. The objects 



i o AN ENQ UIR Y CONCE RNIN U 

are too fine to remain long in the same aspect or situa- 
tion ; and must be apprehended in an instant, by a 
superior penetration, derived from nature, and im- 
proved by habit and reflexion. It becomes, therefore, 
no inconsiderable part of science barely to know the 
different operations of the mind, to separate them from 
each other, to class them under their proper heads, 
and to correct all that seeming disorder, in which they 
lie involved, when made the object of reflexion and en- 
quiry. This talk of ordering and distinguishing, which 
has no merit, when performed with regard to external 
bodies, the objects of our senses, rises in its value, 
when directed towards the operations of the mind, in 
proportion to the difficulty and labour, which we meet 
with in performing it. And if we can go no farther 
than this mental geography, or delineation of the dis- 
tinct parts and powers of the mind, it is at least a 
satisfaction to go so far ; and the more obvious this 
science may appear (and it is by no means obvious) 
the more contemptible still must the ignorance of it 
be esteemed, in all pretenders to learning and philos- 
ophy. 

Nor can there remain any suspicion, that this sci- 
ence is uncertain and chimerical ; unless we should 
entertain such a scepticism as is entirely subversive oi 
all speculation, and even action. It cannot be doubted, 
that the mind is endowed with several powers and 
faculties, that these powers are distinct from each 
other, that what is really distinct to the immediate 
perception may be distinguished by reflexion; and 
consequently, that there is a truth and falsehood in 
all propositions on this subject, and a truth and false- 
hood, which lie not beyond the compass of human 
understanding. There are many obvious distinctions 



HUMAN UNDERSTANDING. tt 

of this kind, such as those between the will and un- 
derstanding, the imagination and passions, which fall 
within the comprehension of every human creature ; 
and the finer and more philosophical distinctions are 
no less real and certain, though more difficult to be 
comprehended. Some instances, especially late ones, 
of success in these enquiries, may give us a juster no- 
tion of the certainty and solidity of this branch of 
learning. And shall we esteem it worthy the labour 
of a philosopher to give us a true system of the plan- 
ets, and adjust the position and order of those remote 
bodies ; while we affect to overlook those, who, with 
so much success, delineate the parts of the mind, in 
which we are so intimately concerned ? 

But may we not hope, that philosophy, if culti- 
vated with care, and encouraged by the attention of 
the public, may carry its researches still farther, and 
discover, at least in some degree, the secret springs 
and principles, by which the human mind is actuated 
in its operations ? Astronomers had long contented 
themselves with proving, from the phaenomena, the 
true motions, order, and magnitude of the heavenly 
bodies: Till a philosopher, at last, arose, who seems, 
from the happiest reasoning, to have also determined 
the laws and iorces, by which the revolutions of the 
planets are governed and directed. The like has been 
performed with regard to other parts of nature. And 
there is no reason to despair of equal success in our 
enquiries concerning the mental powers and economy, 
if prosecuted with equal capacity and caution. It is 
probable, that one operation and principle of the mind 
depends on another; which, again, may be resolved 
into one more general and universal ; And how far 
these researches may possibly be carried, it will be 



la AN ENQUIRY CONCERNING 

difficult for us, before, or even after, a careful trial 
exactly to determine. This is certain, that attempt 
of this kind are every day made even by those wht, 
philosophize the most negligently: And nothing can 
be more requisite than to enter upon the enterprize 
with thorough care and attention ; that, if it lie within 
the compass of human understanding, it may at last 
be happily achieved ; if not, it may, however, be re 
jected with some confidence and security. This last 
conclusion, surely, is not desirable ; nor ought it to be 
embraced too rashly. For how much must we dimin- 
ish from the beauty and value of this species of phi- 
losophy, upon such a supposition? Moralists have 
hitherto been accustomed, when they considered the 
vast multitude and diversity of those actions that ex- 
cite our approbation or dislike, to search for some 
common principle, on which this variety of sentiments 
might depend. And though they have sometimes car- 
ried the matter too far, by their passion for some one 
general principle ; it must, however, be confessed, 
that they are excusable in expecting to find some gen- 
eral principles, into which all the vices and virtues 
were justly to be resolved. The like has been the 
endeavour of critics, logicians, and even politicians : 
Nor have their attempts been wholly unsuccessful ; 
though perhaps longer time, greater accuracy, and 
more ardent application may bring these sciences still 
nearer their perfection. To throw up at once all pre- 
tensions of this kind may justly be deemed more rash, 
precipitate, and dogmatical, than even the boldest and 
most affirmative philosophy, that has ever attempted 
to impose its crude dictates and principles on man- 
kind. 

What though these reasonings concerning human 



HUMAN UNDERSTANDING. 13 

nature seem abstract, and of difficult comprehension ? 
This affords no presumption of their falsehood. On 
the contrary, it seems impossible, that what has hith- 
erto escaped so many wise and profound philosophers 
can be very obvious and easy. And whatever pains 
these researches may cost us, we may think ourselves 
sufficiently rewarded, not only in point of profit but of 
pleasure, if, by that means, we can make any addition 
to our stock of knowledge, in subjects of such un- 
speakable importance. 

But as, after all, the abstractedness of these specu- 
lations is no recommendation, but rather a disadvan- 
tage to them, and as this difficulty may perhaps be 
surmounted by care and art, and the avoiding of all 
unnecessary detail, we have, in the following enquiry, 
attempted to throw some light upon subjects, from 
which uncertainty has hitherto deterred the wise, and 
obscurity the ignorant. Happy, if we can unite the" 
boundaries of the different species of philosophy, by 
reconciling profound enquiry with clearness, and truth 
with novelty ! And still more happy, if reasoning in 
this easy manner, we can undermine the foundations 
of an abstruse philosophy, which seems to have hith- 
erto served only as a shelter to superstition, and a 
cover to absurdity and error I 



SECTION II. 

OF THE ORIGIN OF IDEAS. 

EVERY one will readily allow, that there is a con- 
siderable difference between the perceptions of 
the mind, when a man feels the pain of excessive heat, 
or the pleasure of moderate warmth, and when he aft- 
erwards recalls to his memory this sensation, or antic- 
ipates it by his imagination. These faculties may 
mimic or copy the perceptions of the senses ; but they 
never can entirely reach the force and vivacity of the 
original sentiment. The utmost we say of them, even 
when they operate with greatest vigour, is, that they 
represent their object in so lively a manner, that we 
could almost say we feel or see it : But, except the 
mind be disordered by disease or madness, they never 
can arrive at such a pitch of vivacity, as to render 
these perceptions altogether undistinguishable. All 
the colours of poetry, however splendid, can never 
paint natural objects in such a manner as to make the 
description be taken for a real landskip. The most 
lively thought is still inferior to the dullest sensation. 
We may observe a like distinction to run through 
all the other ^perceptions of the mind. A man in a fit 
of anger, is actuated in a very different manner from 
one who only thinks of that emotion. If you tell me, 
that any person is in love, I easily understand your 
meaning, and form a just conception of his situation ; 
but never can mistake that conception for the real 



HUMAN UNDERSTANDING. 15 

disorders and agitations of the passion. When we 
reflect on our past sentiments and affections, our 
thought is a faithful mirror, and copies its objects 
truly ; but the colours which it employs are faint and 
dull, in comparison of those in which our original per- 
ceptions were clothed. It requires no nice discern- 
ment or metaphysical head to mark the distinction be- 
tween them. 

Here therefore we may divide all the perceptions 
of the mind into two classes or species, which are dis- 
tinguished by their different degrees of force and vivac- 
ity. The less forcible and lively are commonly de- 
nominated Thoughts or Ideas. The other species want 
a name in our language, and in most others ; I sup- 
pose, because it was not requisite for any, but philos- 
ophical purposes, to rank them under a general term 
or appellation. Let us, therefore, use a little freedom, 
and call them Impressions ; employing that word in a 
sense somewhat different from the usual. By the term 
impression, then, I mean al l our more liv ely percep- 
tions, when we hear, or see, or feel, or love, or hate, 



or desire, or will. And impressions are distinguished 
from ideas, which are the less lively perceptions, of 
which we are conscious, when we reflect on any of 
those sensations or movements above mentioned. 

Nothing, at first view, may seem more unbounded 
than the thought of man, which not only escapes all 
human power and authority, but is not even restrained 
within the limits of nature and reality. To form mon- 
sters, and join incongruous shapes and appearances, 
costs the imagination no more trouble than to conceive 
the most natural and familiar objects. And while the 
body is confined to one planet, along which it creeps 
with pain and difficulty ; the thought can in an instant 



9 



1 6 AN ENQ UIR Y CONCERNING 

transport us into the most distant regions of the uni- 
verse ; or even beyond the universe, into the un- 
bounded chaos, where nature is supposed to lie in total 
confusion. What never was seen, or heard of, may 
yet be conceived ; nor is any thing beyond the power 
of thought, except what implies an absolute contra- 
diction. 

But though our thought seems to possess this un- 
bounded liberty, we shall find, upon a nearer examina- 
tion, that it is really confined within very narrow lim- 
its, and that all this creative power of the mind 
amounts to no more than the faculty of compounding 
transposing, augmenting, or diminishing the materials 
afforded us by the senses and experience. When we 
think of a golden mountain, we only join two consist- 
ent ideas, gold, and mountain, with which we were 
formerly acquainted. A virtuous horse we can con- 
ceive ; because, from our own feeling, we can conceive 
virtue ; and this we may unite to the figure and shape 
of a horse, which is an animal familiar t to us. In short, 
all the materials of thinking are derived either from 
our outward or inward sentiment : the mixture and 
composition of these belongs alone to the mind and 
will. Or, to express myself in philosophical language, 
all our ideas or more feeble perceptions are copies of 
our impressions or more lively ones. 

To prove this, the two following arguments will, 
I hope, be sufficient. First, when we analyze our 
thoughts or ideas, however compounded or sublime, 
we always find that they resolve themselves into such 
simple ideas as were copied from a precedent feeing 
or sentiment. Even those ideas, which, at first view, 
seem the most wide of this origin, are found, upon a 
nearer scrutiny, to be derived from it. The idea of 



HUMAN - UNDERSTANDING. 17 

God, as meaning an infinitely intelligent, wise, and 
good Being, arises from reflecting on the operations of 
our own mind, and augmenting, without limit, those 
qualities of goodness and wisdom. We may prosecute 
this enquiry to what length we please ; where we shall 
always find, that every idea which we examine is copied 
from a similar impression. Those who would assert 
that this position is not universally true nor without 
exception, have only one, and that an easy method of 
refuting it; by producing that idea, which, in their 
opinion, is not derived from this source. It will then 
be incumbent on us, if we would maintain our doc- 
trine, to produce the impression, or lively perception, 
which corresponds to it. 

Secondly. If it happen, from a defect of the or- 
gan, that a man is not susceptible of any species of 
sensation, we always find that he is as little suscept- 
ible of the correspondent ideas. A blind man can form 
no notion of colours; a deaf man of sounds. Restore 
either of them that sense in which he is deficient ; by 
opening this new inlet for his sensations, you also 
open an inlet for the ideas ; and he finds no difficulty 
in conceiving these objects. The case is the same, if 
the object, proper for exciting any sensation, has never 
been applied to the organ. A Laplander or Negro 
has no notion of the relish of wine. And though there 
are few or no instances of a like deficiency in the 
mind, where a person has never felt or is wholly in- 
capable of a sentiment or passion that belongs to his 
species; yet we find the same observation to take place 
in^a less degree. A man of mild manners can form no 
idea of inveterate revenge or cruelty ; nor can a selfish 
heart easily conceive the heights of friendship and 
generosity. It is readily allowed, that other beings 



W 



18 A AT ENFQ U1R V COtfCERNltfLr 

may possess many senses of which we can have no 
conception ; because the ideas of them have never 
been introduced to us in the only manner by which an 
idea can have access to the mind, to wit, by the actual 
feeling and sensation. 

There is, however, one contradictory phenomenon, 
which may prove that it is not absolutely impossible 
for ideas to arise, independent of their correspondent 
impressions. I believe it will readily be allowed, that 
the several distinct ideas of colour, which enter by the 
eye, or those of sound, which are conveyed by the ear, 
are really different from each other ; though, at the 
same time, resembling. Now if this be true of differ- 
ent colours, it must be no less so of the different 
shades of the same colour ; and each shade produces 
a distinct idea, independent of the rest. For if this 
should be denied, it is possible, by the continual gra- 
dation of shades, to run a colour insensibly into what 
is most remote from it; and if you will not allow any 
of the means to be different, 3 ou cannot, without ab- 
surdity, deny the extremes to be the same. Suppose, 
therefore, a person to have enjoyed his sight for thirty 
years, and to have become perfectly acquainted with 
colours of all kinds except one particular shade of 
blue, for instance, which it never has been his fortune 
to meet with. Let all the different shades of that 
colour, except that single one, be placed before him, 
descending gradually from the deepest to the lightest; 
it is plain that he will perceive a blank, where that 
shade is wanting, and will be sensible that there is a 
greater distance in that place between the contiguous 
colours than in any other. Now I ask, whether it be 
possible for him, from his own imagination, to supply 
this deficiency, and raise up to himself the idea of that 



1WMAN UNDERSTANDING. 19 

particular shade, though it had never been conveyed 
to him by his senses? I believe there are few but will 
be of opinion that he can : and this may serve as a 
proof that the simple ideas are not always, in every 
instance, derived from the correspondent impressions; 
though this instance is so singular, that it is scarcely 
worth our observing, and does not merit that for it 
alone we should alter our general maxim. 

Here, therefore, is a proposition, which not only 
seems, in itself, simple and intelligible; but, if a 
proper use were made of it, might render every dis- 
pute equally intelligible, and banish all that jargon, 
which has so long taken possession of metaphysical 
reasonings, and drawn disgrace upon them. All ideas, 
especially abstract ones, are naturally faint and ob- 
scure : the mind has but a slender hold of them : they 
are apt to be confounded with other resembling ideas ; 
and when we have often employed any term, though 
without a distinct meaning, we are apt to imagine it 
has a determinate idea annexed to it. On the con- 
trary, all impressions, that is, all sensations, either 
outward or inward, are strong and vivid : the limits 
between them are more exactly determined : nor is it 
easy to fall into any error or mistake with regard to 
them. When we entertain, therefore, any suspicion 
that a philosophical term is employed without any 
meaning or idea (as is but too frequent), we need but 
enquire, from what impression is that supposed idea 
derived? And if it be impossible to assign any, this 
will serve to confirm our suspicion. 1 By bringing 

lit is probable that no more was meant by those, who denied innate 
ideas, than that all ideas were copies of our impressions; though it must be 
confessed, that the terms, which they employed, were not chosen with sucli 
caution, nor so exactly defined, as to prevent all mistakes about their doc 
trine. For what is meant by innate ? If innate be equivalent to natural, then 



20 AN ENQ UTR V CONCERNING 

ideas into so clear a light we may reasonably hope 
to remove all dispute, which may arise, concerning 
their nature and reality. 

all the perceptions and ideas of the mind must be allowed to be innate or 
natural, in whatever sense we take the latter word, whether in opposition to 
what is uncommon, artificial, or miraculous. If by innate be meant, contem- 
porary to our birth, the dispute seems to be frivolous; nor is it worth while 
to enquire at what time thinking begins, whether before, at, or after our 
birth. Again, the word idea, seems to be commonly taken in a very loose 
sense, by Locke and others; as standing for any of our perceptions, our sen- 
sations and passions, as well as thoughts. Now in this sense, I should desire 
to know, what can be meant by asserting, that self-love, or resentment of in- 
juries, or the passion between the sexes is not innate ? 

But admitting these terms, impressions and ideas, in the sense above ex 
plained, and understanding by innate, what is original or copied from no pre 
cedent perception, then may we assert that all our impressions are innate 
and our ideas not innate. 

To be ingenuous, I must own it to be my opinion, that Locke was be 
trayed into this question by the schoolmen, who, making use of undefined 
terms, draw out their disputes to a tedious length, without ever touching the 
point in question. A like ambiguity and circumlocution seem to run through 
that philosopher's reasonings on this as well as most other subjects. 



SECTION III. 

OF THE ASSOCIATION OF IDEAS. 

IT is evident that there is a principle of connexion 
between the different thoughts or ideas of the 
mind, and that, in their appearance to the memory or 
imagination, they introduce each other with a certain 
degree of method and regularity. In our more serious 
thinking or discourse this is so observable that any 
particular thought, which breaks in upon the regular 
tract or chain of ideas, is immediately remarked and 
rejected. And even in our wildest and most wander- 
ing reveries, nay in our very dreams, we shall find, if 
we reflect, that the imagination ran not altogether at 
adventures, but that there was still a connexion up- 
held among the different ideas, which succeeded each 
other. Were the loosest and freest conversation to be 
transcribed, there would immediately be observed 
something which connected it in all its transitions. 
Or where this is wanting, the person who broke the 
thread of discourse might still inform you, that there 
had secretly revolved in his mind a succession of 
thought, which had gradually led him from the sub- 
ject of conversation. Among different languages, even 
where we cannot suspect the least connexion or com- 
munication, it is found, that the words, expressive of 
ideas, the most compounded, do yet nearly correspond 
to each other: a certain proof that the simple ideas, 
comprehended in the compound ones, were bound to" 



22 AN ENQUIRY CONCERNING 

gether by some universal principle, which had an 
equal influence on all mankind. 

Though it be too obvious to escape observation, 
that different ideas are connected together ; I do not 
find that any philosopher has attempted to enumerate 
or class all the principles of association ; a subject, 
however, that seems worthy of curiosity. To me, there 
appear to be only three principles of connexion among 
ideas, namely, Resemblance, Contiguity in time or place, 
and Cause or Effect. 

That these principles serve to connect ideas will 
not, I believe, be much doubted. A picture naturally 
leads our thoughts to the original : 1 the mention of 
one apartment in a building naturally introduces an 
enquiry or discourse concerning the others: 2 and if 
we think of a wound, we can scarcely forbear reflect- 
ing on the pain which follows it. 3 But that this 
enumeration is complete, and that there are no other 
principles of association except these, may be difficult 
to prove to the satisfaction of the reader, or even to a 
man's own satisfaction. All we can do, in such cases, 
is to run over several instances, and examine carefully 
the principle which binds the different thoughts to 
each other, never stopping till we render the principle 
as general as possible. 4 The more instances we exam- 
ine, and the more care we employ, the more assurance 
shall we acquire, that the enumeration, which we form 
from the whole, is complete and entire. 

1 Resemblance. 2 Contiguity. 3 Cause and effect. 

4 For instance, Contrast or Contrariety is also a connexion among Ideas 
but it may, perhaps, be considered as a mixture of Causation and Resem- 
blance. Where two objects are contrary, the one destroys the other; that is, 
the cause of its annibilaiicn, and the idea of the annihilation of an object 
implies the idea of its former existence. 



SECTION IV. 

SCEPTICAL DOUBTS CONCERNING THE OPERATIONS 
OF THE UNDERSTANDING. 

Part I. 

ALL the objects of human reason or enquiry may 
.. naturally be divided into two kinds, to wit, Rela- 
tions of Ideas, and Matters of Fact. Of the first kind are 
the sciences of Geometry, Algebra, and Arithmetic; 
and in short, every affirmation which is either intui- 
tively or demonstratively certain. That the square of 
the hypothenuse is equal to the squares of the two sides, is 
a proposition which expresses a relation between these 
figures. That three times five is equal to the half of 
thirty, expresses a relation between these numbers. 
Propositions of this kind are discoverable by the mere 
operation of thought, without dependence on what is 
anywhere existent in the universe. Though there 
never were a circle or triangle in nature, the truths 
demonstrated by Euclid would for ever retain their 
certainty and evidence. 

Matters of fact, which are the second objects of 
human reason, are not ascertained in the same man- 
ner ; nor is our evidence of their truth, however great, 
of a like nature with the foregoing. The contrary of 
every matter of fact is still possible ; because it can 
never imply a contradiction, and is conceived by the 
mind with the same facility and distinctness, as if ever 



2 \ AN ENQ UIR V CONCERNING 

so conformable to reality. That the sun will not rist 
to-morrow is no less intelligible a proposition, and 
implies no more contradiction than the affirmation, 
that it will rise We should in vain, therefore, attempt 
to demonstrate its falsehood. Were it demonstratively 
false, it would imply a contradiction, and could never 
be distinctly conceived by the mind. 

It may, therefore, be a subject worthy of curiosity, 
to enquire what is the nature of that evidence which 
assures us of any rea? existence and matter of fact, 
beyond the present testimony of our senses, or the 
records of our memory, This part of philosophy, it 
is observable, has been little cultivated, either by the 
ancients or moderns ; and therefore our doubts and 
errors, in the prosecution of so important an enquiry, 
may be the more excusable ; while we march through 
such difficult paths without any guide or direction. 
They may even prove useful, by exciting curiosity, 
and destroying that implicit faith and security, which 
is the bane of all reasoning and free enquiry. The dis- 
covery of defects in the common philosophy, if any 
such there be, will not, I presume, be a discourage- 
ment, but rather an incitement, as is usual, to attempt 
something more full and satisfactory than has yet been 
proposed to the public. 

Ail reasonings concerning matter of fact seem to 
be founded on the relation of Cause and Effect. By 
means of that relation alone we can go beyond the 
evidence of our memory and senses. If you were to 
ask a man, why he believes any matter of fact, which 
is absent; for instance, that his friend is in the coun- 
try, or in France ; he would give you a reason ; and 
this reason would be some other fact; as a letter re- 
ceived from him, or the knowledge of his former res- 



HUMAN UNDERSTANDING. 25 

ofutions and promises. A man finding a watch or any- 
other machine in a desert island, would conclude that 
there had once been men in that island. All our rea- 
sonings concerning fact are of the same nature. And 
here it is constantly supposed that there is a connexion 
between the present fact and that which is inferred 
from it. Were there nothing to bind them together, 
the inference would be entirely precarious. The hear- 
ing of an articulate voice and rational discourse in the 
dark assures us of the presence of some person : 
Why ? because these are the effects of the human make 
and fabric, and closely connected with it. If we anat- 
omize all the other reasonings of this nature, we shall 
find that they are founded on the relation of cause and 
effect, and that this relation is either near or remote, 
direct or collateral. Heat and light are collateral 
effects of fire, and the one effect may justly be inferred 
from the other. 

If we would satisfy ourselves, therefore, concern- 
ing the nature of that evidence, which assures us of 
matters of fact, we must enquire how we arrive at the 
knowledge of cause and effect. 

I shall venture to affirm, as a general proposition, 
which admits of no exception, that the knowledge of 
this relation is not, in any instance, attained by rea- 
sonings a priori; but arises entirely from experience, 
when we find that any particular objects are constantly 
conjoined with each other. Let an object be presented 
to a man of ever so strong natural reason and abilities ; 
if that object be entirely new to him, he will not be 
able, by the most accurate examination of its sensible 
qualities, to discover any of its causes or effects. 
Adam, though his rational faculties be supposed, at 
the very first, entirely perfect, could not have inferred 



26 AN ENQUIRY CONCERNING 

from the fluidity and transparency of water that it 
would suffocate him, or from the light and warmth of 
fire that it would consume him. No object ever dis- 
covers, by the qualities which appear to the senses, 
either the causes which produced it, or the effects 
which will arise from it ; nor can our reason, un- 
assisted by experience, ever draw any inference con 
cerning real existence and matter of fact. 

This proposition, that causes and effects are discover- 
able, not by reason but by experience, will readily be ad- 
mitted with regard to such objects, as we remember 
to have once been altogether unknown to us; since 
we must be conscious of the utter inability, which we 
then lay under, of foretelling what would arise from 
them. Present two smooth pieces of marble to a man 
who has no tincture of natural philosophy ; he will 
never discover that they will adhere together in such 
a manner as to require great force to separate them in 
a direct line, while they make so small a resistance to 
a lateral pressure. Such events, as bear little analogy 
to the common course of nature, are also readily con- 
fessed to be known only by experience ; nor does any 
man imagine that the explosion of gunpowder, or the 
attraction of a loadstone, could ever be discovered by 
arguments a priori. In like manner, when an effect 
is supposed to depend upon an intricate machinery or 
secret structure of parts, we make no difficulty in at- 
tributing all our knowledge of it to experience. Who 
will assert that he can give the ultimate reason, why 
milk or bread is proper nourishment for a man, not 
for a lion or a tiger? 

But the same truth may not appear, at first sight, 
to have the same evidence with regard to events, 
which have become familiar to us from our first ap< 



HUMAN UNDERSTANDING. 27 

pearance in the world, which bear a close analogy to 
the whole course of nature, and which are supposed 
to depend on the simple qualities of objects, without 
any secret structure of parts. We are apt to imagine 
that we could discover these effects by the mere opera- 
tion of our reason, without experience. We fancy, that 
were we brought on a sudden into this world, we could 
at first have inferred that one Billiard-ball would com- 
municate motion to another upon impulse ; and that 
we needed not to have waited for the event, in order 
to pronounce with certainty concerning it. Such is 
the influence of custom, that, where it is strongest, it 
not only covers our natural ignorance, but even con- 
ceals itself, and seems not to take place, merely be- 
cause it is found in the highest degree. 

But to convince us that all the laws of nature, and 
all the operations of bodies without exception, are 
known only by experience, the following reflections 
may, perhaps, suffice. Were any object presented to 
us, and were we required to pronounce concerning the 
effect, which will result from it, without consulting 
past observation ; after what manner, I beseech you, 
must the mind proceed in this operation ? It must in- 
vent or imagine some event, which it ascribes to the 
object as its effect ; and it is plain that this invention 
must be entirely arbitrary. The mind can never pos- 
sibly find the effect in the supposed cause, by the most 
accurate scrutiny and examination. For the effect is 
totally different from the cause, and consequently can 
never be discovered in it. Motion in the second Bil- 
liard-ball is a quite distinct event from motion in the 
first; nor is there anything in the one to suggest the 
smallest hint of the other. A stone or piece of metal 
raised into the air, and left without any support, im- 



28 AN ENQUIRY CONCERNING 

mediately falls . but to consider the matter a priori, is 
there anything we discover in this situation which can 
beget the idea of a downward, rather than an upward, 
or any other motion, in the stone or metal? 

And as the first imagination or invention of a par- 
ticular effect, in all natural operations, is arbitrary, 
where we consult not experience ; so must we also es- 
teem the supposed tie or connexion between the cause 
and effect, which binds them together, and renders it 
impossible that any other effect could result from the 
operation of that cause. When I see, for instance, 
a Billiard-ball moving in a straight line towards an- 
other ; even suppose motion in the second ball should 
by accident be suggested to me, as the result of their 
contact or impulse ; may I not conceive, that a hun- 
dred different events might as well follow from that 
cause ? May not both these balls remain at absolute 
rest ? May not the first ball return in a straight line, 
or leap off from the second in any line or direction ? 
All these suppositions are consistent and conceivable. 
Why then should we give the preference to one, which 
is no more consistent or conceivable than the rest ? 
All our reasonings a priori will never be able to show 
us any foundation for this preference. 

In a word, then, every effect is a distinct event 
from its cause. It could not, therefore, be discovered 
in the cause, and the first invention or conception of 
it, a priori, must be entirely arbitrary. And even after 
it is suggested, the conjunction of it with the cause 
must appear equally arbitrary; since there are always 
many other effects, which, to reason, must seem fully 
as consistent and natural. In vain, therefore, should 
we pretend to determine any single event, or infer any 



HUMAN UNDERSTANDING. 29 

cause or effect, without the assistance of observation 
and experience. 

Hence we may discover the reason why no philos- 
opher, who is rational and modest, has ever pretended 
to assign the ultimate cause of any natural operation, 
or to show distinctly the action of that power, which 
produces any single effect in the universe. It is con- 
fessed, that the utmost effort of human reason is to re- 
duce the principles, productive of natural phenomena, 
to a greater simplicity, and to resolve the many par- 
ticular effects into a few general causes, by means of 
reasonings from analogy, experience, and observation. 
But as to the causes of these general causes, we should 
in vain attempt their discovery ; nor shall we ever be 
able to satisfy ourselves, by any particular explication 
of them. These ultimate springs and principles are 
totally shut up from human curiosity and enquiry. 
Elasticity, gravity, cohesion of parts, communication 
of motion by impulse; these are probably the ultimate 
causes and principles which we ever discover in nature; 
and we may esteem ourselves sufficiently happy, if, by 
accurate inquiry and reasoning, we can trace up the 
particular phenomena to, or near to, these general 
principles. The most perfect philosophy of the natural 
kind only staves off our ignorance a little longer : as 
perhaps the most perfect philosophy of the moral or 
metaphysical kind serves only to discover larger por- 
tions of it. ^Thus the observation of human blindness 
and weakness is the result of all philosophy, and meets 
us at every turn, in spite of our endeavours to elude 
or avoid it. ) 

Nor is geometry, when taken into the assistance of 
natural philosophy, ever able to remedy this defect, or 
lead us into the knowledge of ultimate causes, by all 



30 AN ENQ UIR Y CONCERNING 

that accuracy of reasoning for which it is so justly cel- 
ebrated. Every part of mixed mathematics proceeds 
upon the supposition that certain laws are established 
by nature in her operations ; and abstract reasonings 
are employed, either to assist experience in the discov- 
ery of these laws, or to determine their influence in 
particular instances, where it depends upon any pre- 
cise degree of distance and quantity. Thus, it is a law _ 
of motion, discovered by experience, that the moment 
or force of any body in motion is in the compound ra- 
tio or proportion of its solid contents and its velocity ; 
and consequently, that a small force may remove the 
greatest obstacle or raise the greatest weight, if, by 
any contrivance or machinery, we can increase the ve- 
locity of that force, so as to make it an overmatch for 
its antagonist. Geometry assists us in the application 
of this law, by giving us the just dimensions of all the 
parts and figures which can enter into any species of « 
machine ; but still the discovery of the law itself is ow- 
ing merely to experience, and all the abstract reason- 
ings in the world could never lead us one step towards 
the knowledge of it. When we reason a priori, and 
consider merely any object or cause, as it appears to 
the mind, independent of all observation, it never could 
suggest to us the notion of any distinct object, such as 
its effect ; much less, show us the inseparable and in- 
violable connexion between them. A man must be 
very sagacious who could discover by reasoning that 
crystal is the effect of heat, and ice of cold, without 
being previously acquainted with the operation of these 

qualities. 

Part II. 

But we have not yet attained any tolerable satisfac- 
tion with regard to the question first proposed, Each 



HUMAN UNDERSTANDING. 31 

solution still gives rise to a new question as difficult 
as the foregoing, and leads us on to farther enquiries. 
When it is asked, What is the nature of all our reason- 
ings concerning matter of fact ? the proper answer seems 
to be, that they are founded on the relation of cause 
and effect. When again it is asked, What is the foun- 
dation of all our reasonings and conclusions concerning that 
relation ? it may be replied in one word, Experience. 
But if we still carry on our sifting humour, and ask, 
What is the foundation of all conclusions from experience? 
this implies a new question, which may be of more 
difficult solution and explication. Philosophers, that 
give themselves airs of superior wisdom and sufficiency, 
have a hard task when they encounter persons of in- 
quisitive dispositions, who push them from every cor- 
ner to which they retreat, and who are sure at last to 
bring them to some dangerous dilemma. The best ex- 
pedient to prevent this confusion, is to be modest in 
our pretensions ; and even to discover the difficulty 
ourselves before it is objected to us. By this means, 
we may make a kind of merit of our very ignorance. 

I shall content myself, in this section, with an easy 
task, and shall pretend only to give a negative answer 
to the question here proposed. I say then, that, even 
after we have experience of the operations of cause 
and effect, our conclusions from that experience are 
not founded on reasoning, or any process of the under- 
standing. This answer we must endeavour both to ex- 
plain and to defend. 

It must certainly be allowed, that nature has kept 
us at a great distance from all her secrets, and has af- 
forded us only the knowledge of a few superficial qual- 
ities of objects ; while she conceals from us those pow- 
ers and principles on which the influence of those ob- 



32 AN ENQ UIR Y CONCERNING 

jects entirely depends. Our senses inform us of the. 
colour, weight, and consistence of bread ; but neither 
sense nor reason can ever inform us of those qualities 
which fit it for the nourishment and support of a human 
body. Sight or feeling conveys an idea of the actual 
motion of bodies ; but as to that wonderful force or 
power, which would carry on a moving body for ever 
in a continued change of place, and which bodies never 
lose but by communicating it to others; of this we can- 
not form the most distant conception. But notwith- 
standing this ignorance of natural powers 1 and prin- 
ciples, we always presume, when we see like sensible 
qualities, that they have like secret powers, and expect 
that effects, similar to those which we have experienced, 
will follow from them. If a body of like colour and 
consistence with that bread, which we have formerly 
eat, be presented to us, we make no scruple of repeat- 
ing the experiment, and foresee, with certainty, like 
nourishment and support. Now this is a process of 
the mind or thought, of which I would willingly know 
the foundation. It is allowed on all hands that there 
is no known connexion between the sensible qualities 
and the secret powers; and consequently, that the mind 
is not led to form such a conclusion concerning their 
constant and regular conjunction, by anything which it 
knows of their nature. As to past Experience, it can be 
allowed to give direct and certain information of those 
precise objects only, and that precise period of time, 
which fell under its cognizance : but why this experi- 
ence should be extended to future times, and to other 
objects, which, for aught we know, may be only in ap~ 



1 The word. Power, is here used in a loose and popular sense. The more 
accurate explication of it would give additional evidence to this argument 
See Sect. 7. 



HUMAN UNDERSTANDING. 33 

pearance similar; this is the main question on which 
I would insist. The bread, which I formerly eat, nour- 
ished me ; that is, a body of such sensible qualities 
was, at that time, endued with such secret powers : 
but does it follow, that other bread must also nourish 
me at another time, and that like sensible qualities 
must always be attended with like secret powers? The 
consequence seems nowise necessary. At least, it must 
be acknowledged that there is here a consequence 
drawn by the mind; that there is a certain step taken; 
a process of thought, and an inference, which wants 
to be explained. These two propositions are far from 
being the same, I have found that such an object has al- 
ways been attended with such an effect, and I foresee, that 
other objects, which are, in appearance, similar, will be 
attended with similar effects. I shall allow, if you please, 
that the one proposition may justly be inferred from 
the other ; I know, in fact, that it always is inferred. 
But if you insist that the inference is made by a chain 
of reasoning, I desire you to produce that reasoning. 
The connexion between these propositions is not intu- 
itive. There is required a medium, which may enable 
the mind to draw such an inference, if indeed it be 
drawn by reasoning and argument. What that me- 
dium is, I must confess, passes my comprehension ; 
and it is incumbent on those to produce it, who as- 
sert that it really exists, and is the origin of all our 
conclusions concerning matter of fact. 

This negative argument must certainly, in process 
of time, become altogether convincing, if many pene- 
trating and able philosophers shall turn their enquiries 
this way and no one be ever able to discover any con- 
necting proposition or intermediate step, which sup- 
ports the understanding in this conclusion. But as the 



34 AN ENQUlRV CONCERNING 

question is yet new, every reader may not trust so far 
to his own penetration, as to conclude, because an ar- 
gument escapes his enquiry, that therefore it does not 
really exist. For this reason it may be requisite to 
venture upon a more difficult task ; and enumerating 
all the branches of human knowledge, endeavour to 
show that none of them can afford such an argument. 

All reasonings may be divided into two kinds, 
namely, demonstrative reasoning, or that concerning 
relations of idear., and moral reasoning, or that con- 
cerning matter of fact and existence. That there are 
no demonstrative arguments in the case seems evident ; 
since it implies no contradiction that the course of na- 
ture may change, and that an object, seemingly like 
those which we have experienced, may be attended 
with different or contrary effects. May I not clearly 
and distinctly conceive that a body, falling from the 
clouds, and which, in all other respects, resembles 
snow, has yet the taste of salt or feeling of fire ? Is 
there any more intelligible proposition than to affirm, 
that all the trees will flourish in December and Janu- 
ary, and decay in May and June ? Now whatever is 
intelligible, and can be distinctly conceived, implies 
no contradiction, and can never be proved false by any 
demonstrative argument or abstract reasoning a priori. 

If we be, therefore, engaged by arguments to put 
trust in past experience, and make it the standard of 
our future judgement, these arguments must be proba- 
ble only, or such as regard matter of fact and real ex- 
istence, according to the division above mentioned. 
But that there is no argument of this kind, must appear, 
if our explication of that species of reasoning be ad- 
mitted as solid and satisfactory. We have said that 
all arguments concerning existence are founded on the 



HUMAN UNDERSTANDING. 35 

relation of cause and effect ; that our knowledge of that 
relation is derived entirely from experience ; and that 
all our experimental conclusions proceed upon the 
supposition that the future will be conformable to the 
past. To endeavour, therefore, the proof of this last 
supposition by probable arguments, or arguments re- 
garding existence, must be evidently going in a circle, 
and taking that for granted, which is the very point in 
question. 

In reality, all arguments from experience are found- 
ed on the similarity which we discover among natural 
objects, and by which we are induced to expect effects 
similar to those which we have found to follow from 
such objects. And though none but a fool or madman 
will ever pretend to dispute the authority of experi- 
ence, or to reject that great guide of human life, it 
may surely be allowed a philosopher to have so much 
curiosity at least as to examine the principle of human 
nature, which gives this mighty authority to experience, 
and makes us draw advantage from that similarity 
which nature has placed among different objects. 
iFrom causes which appear similar we expect similar 
effects! This is the sum of all our experimental con- 
clusions. Now it seems evident that, if this conclusion 
were formed by reason, it would be as perfect at first, 
and upon one instance, as after ever so long a course 
of experience. But the case is far otherwise. Nothing 
so like as eggs; yet no one, on account of this appear- 
ing similarity, expects the same taste and relish in all 
of them. It is only after a long course of uniform ex- 
periments in any kind, that we attain a firm reliance 
and security with regard to a particular event. Now 
where is that process of reasoning which, from one 
instance, draws a conclusion, so different from that 



36 AN ENQUIRY CONCERNING 

which it infers from a hundred instances that are no- 
wise different from that single one ? This question I 
propose as much for the sake of information, as with 
an intention of raising difficulties. I cannot find, I 
cannot imagine any such reasoning. But I keep my 
mind still open to instruction, if any one will vouch- 
safe to bestow it on me. 

Should it be said that,, from a number of uniform 
experiments, we infer a connexion between the sensi- 
ble qualities and the secret powers ; this, I must con- 
fess, seems the same difficulty, couched in different 
terms. The question still recurs, on what process of 
argument this inference is founded ? Where is the me- 
dium, the interposing ideas, which join propositions 
so very wide of each other ? It is confessed that the 
colour, consistence, and other sensible qualities of 
bread appear not, of themselves, to have any connex- 
ion with the secret powers of nourishment and support. 
For otherwise we could infer these secret powers from 
the first appearance of these sensible qualities, without 
the aid of experience ; contrary to the sentiment of all 
philosophers, and contrary to plain matter of fact. 
Here, then, is our natural state of ignorance with re- 
gard to the powers and influence of all objects. How 
is this remedied by experience ? It only shows us a 
number of uniform effects, resulting from certain ob- 
jects, and teaches us that those particular objects, at 
that particular time, were endowed with such powers 
and forces. When a new object, endowed with simi- 
lar sensible qualities, is produced, we expect similar 
powers and forces, and look for a like effect. From a 
body of like colour and consistence with bread we ex- 
pect like nourishment and support. But this surely 
is a step or progress of the mind, which wants to be 



HUMAN UNDERSTANDING. 37 

explained. When a man says, I have found, in all past 
instances, such sensible qualities conjoined with such secret 1 
powers : And when he says, Similar sensible qualities 
will always be conjoined with similar secret powers, he is 
not guilty of a tautology, nor are these propositions in 
any respect the same. You say that the one proposi- 
tion is an inference from the other. But you must con- 
fess that the inference is not intuitive ; neither is it 
demonstrative : Of what nature is it, then ? To say it 
is experimental, is begging the question. For all in- 
ferences from experience suppose, as their foundation, 
that the future will resemble the past, and that similar 
powers will be conjoined with similar sensible quali- 
ties. If there be any suspicion that the course of na- 
ture may change, and that the past may be no rule for 
the future, all experience becomes useless, and can 
give rise to no inference or conclusion. It is impossi- 
ble, therefore, that any arguments from experience can 
prove this resemblance of the past to the future; since 
all these arguments are founded on the supposition of 
that resemblance. Let the course of things be allowed 
hitherto ever so regular ; that alone, without some new 
argument or inference, proves not that, for the future, 
it will continue so. In vain do you pretend to have 
learned the nature of bodies from your past experience. 
Their secret nature, and consequently all their effects 
and influence, may change, without any change in their 
sensible qualities. This happens sometimes, and with 
regard to some objects : Why may it happen always, 
and with regard to all objects ? What logic, what 
process of argument secures you against this supposi- 
tion ? My practice, you say, refutes my doubts. But 
you mistake the purport of my question. As an agent, 
I am quite satisfied in the point ; but as a philosopher, 



38 AN ENQUIRY CONCERNING 

who has some share of curiosity, I will not say scep- 
ticism, I want to learn the foundation of this inference. 
No reading, no enquiry has yet been able to remove 
my difficulty, or give me satisfaction in a matter of 
such importance. Can I do better than propose the 
difficulty to the public, even though, perhaps, I have 
small hopes of obtaining a solution ? We shall, at 
least, by this means, be sensible of our ignorance, if 
we do not augment our knowledge. 

I must confess that a man is guilty of unpardonable 
arrogance who concludes, because an argument has 
escaped his own investigation, that therefore it does 
not really exist. 1 must also confess that, though all 
the learned, for several ages, should have emplo}^ed 
themselves in fruitless search upon any subject, it may 
still, perhaps, be rash to conclude positively that the 
subject must, therefore, pass all human comprehension. 
Even though we examine all the sources of our knowl- 
edge, and conclude them unfit for such a subject, there 
may still remain a suspicion, that the enumeration is 
not complete, or the examination not accurate. But 
with regard to the present subject, there are some con- 
siderations which seem to remove all this accusation 
of arrogance or suspicion of mistake. 

It is certain that the most ignorant and stupid 
peasants — nay infants, nay even brute beasts — improve 
by experience, and learn the qualities of natural ob- 
jects, by observing the effects which result from them. 
When a child has felt the sensation of pain from touch- 
ing the flame of a candle, he will be careful not to put 
his hand near any candle; but will expect a similar 
effect from a cause which is similar in its sensible qual- 
ities and appearance. If you assert, therefore, that 
the understanding of the child is led into this conclu- 



HUMAH UNDERSTANDING 39 

sion by any process of argument or ratiocination, I may 
justly require you to produce that argument ; nor have 
you any pretense to refuse so equitable a demand. You 
cannot say that the argument is abtruse, and may pos- 
sibly escape your enquiry ; since you confess that it is 
obvious to the capacity of a mere infant. If you hesi- 
tate, therefore, a moment, or if, after reflection, you pro- 
duce any intricate or profound argument, you, in a man- 
ner, give up the question, and confess that it is not 
reasoning which engages us to suppose the past re- 
sembling the future, and to expect similar effects from 
causes which are, to appearance, similar. This is the 
proposition which I intended to enforce in the present 
section. If I be right, I pretend not to have made any 
mighty discovery. And if I be wrong, I must acknowl- 
edge myself to be indeed a very backward scholar ; 
since I cannot now discover an argument which, it 
seems, was perfectly familiar to me long before I was 
out of my cradle. 



SECTION V. 

SCEPTICAL SOLUTION OF THESE DOUBTS. 

Part I. 

THE passion for philosophy, like that for religion, 
seems liable to this inconvenience, that, though it 
aims at the correction of our manners, and extirpation 
of our vices, it may only serve, by imprudent manage- 
ment, to foster a predominant inclination, and push 
the mind, with more determined resolution, towards 
that side which already draws too much, by the bias 
and propensity of the natural temper. It is certain 
that, while we aspire to the magnanimous firmness of 
the philosophic sage, and endeavour to confine our 
pleasures altogether within our own minds, we may, 
at last, render our philosophy like that of Epictetus, 
and other Stoics, only a more refined system of selfish- 
ness, and reason ourselves out of all virtue as well as 
social enjoyment. While we study with attention the 
vanity of human life, and turn all our thoughts towards 
the empty and transitory nature of riches and honours, 
we are, perhaps, all the while flattering our natural 
indolence, which, hating the bustle of the world, and 
drudgery of business, seeks a pretence of reason to 
give itself a full and uncontrolled indulgence. There 
is, however, one species of philosophy which seems 
little liable to this inconvenience, and that because it 
strikes in with no disorderly passion of the human 



HUMAN UNDERSTANDING. 41 

mind, nor can mingle itself with any natural affection 
or propensity; and that is the Academic or Sceptical 
philosophy. The academics always talk of doubt and 
suspense of judgement, of danger in hasty determina- 
tions, of confining to very narrow bounds the enquiries 
of the understanding, and of renouncing all specula- 
tions which lie not within the limits of common life 
and practice. Nothing, therefore, can be more con- 
trary than such a philosophy to the supine indolence 
of the mind, its rash arrogance, its lofty pretensions, 
and its superstitious credulity. Every passion is mor- 
tified by it, except the love of truth ; and that passion 
never is, nor can be, carried to too high a degree. It 
is surprising, therefore, that this philosophy, which, 
in almost every instance, must be harmless and inno- 
cent, should be the subject of so much groundless re- 
proach and obloquy. But, perhaps, the very circum- 
stance which renders it so innocent is what chiefly 
exposes it to the public hatred and resentment. By 
flattering no irregular passion, it gains few partizans: 
By c pposing so many vices and follies, it raises to 
itself abundance of enemies, who stigmatize it as 
libertine, profane, and irreligious. 

Nor need we fear that this philosophy, while it en- 
deavours to limit our enquiries to common life, should 
ever undermine the reasonings of common life, and 
carry its doubts so far as to destroy all action, as well 
as speculation. \ Nature will always maintain her rights, 
and prevail in "the end over any abstract reasoning 
whatsoever^ Though we should conclude, for instance, 
as in the foregoing section, that, in all reasonings from 
experience, there is a step taken by the mind which is 
not supported by any argument or process of the un- 
derstanding ; there is no danger that these reasonings, 



v^ 



42 AN ENQUIRY CONCERNING 

on which almost all knowledge depends, will ever be 
affected by such a discovery. If the mind be not en- 
gaged by argument to make this step, it must be in- 
duced by some other principle of equal weight and 
authority ; and that principle will preserve its influence 
as long as human nature remains the same. What 
that principle is may well be worth the pains of enquiry. 

Suppose a person, though endowed with the strong- 
est faculties of reason and reflection, to be brought on 
a sudden into this world ; he would, indeed, immedi- 
ately observe a continual succession of objects, and 
one evenWfollowing another; but he would not be able 
to discover anything farther, f He would not, at first, 
by any reasoning, be able to reach the idea of cause 
and effectj since the particular powers, by which all 
natural operations are performed, never appear to thi 
senses; nor is it reasonable to conclude, merely be- 
cause one event, in one instance, precedes another, 
that therefore the one is the cause, the other the effect. 
Their conjunction may be arbitrary and casual. There 
may be no reason to infer the existence of one from 
the appearance of the other. And in a word, such a 
person, without more experience, could never employ 
his conjecture or reasoning concerning any matter of 
fact, or be assured of anything beyond what was im- 
mediately present to his memory and senses. 

Suppose, again, that he has acquired more experi- 
ence, and has lived so long in the world as to have ob- 
served familiar objects or events to be constantly con- 
joined together; what is the consequence of this ex- 
perience ? He immediately infers the existence of one 
object from the appearance of the other. Yet he has 
not, by all his experience, acquired any idea or knowl- 
edge of the secret power by which the one object pro- 



HUMAN UNDERSTANDING. 43 

duces the other; nor is it, by any process of reasoning, 
he is engaged to draw this inference. But still he finds 
himself determined to draw it : And though he should 
be convinced that his understanding has no part in 
the operation, he would nevertheless continue in the 
same course of thinking. There is some other princi- 
ple which determines him to form such a conclusion. 
This principle is Custom or Habit. For wherever 
the repetition of any particular act or operation pro- 
duces a propensity to renew the same act or operation, 
without being impelled by any reasoning or process of 
the understanding, we always say, that this propensity 
is the effect of Custom. By employing that word, we- 
pretend not to have given the ultimate reason of such 
a propensity. We only point out a principle of human 
nature, which is universally acknowledged, and which 
is well known by its effects. Perhaps we can push our 
enquiries no farther, or pretend to give the cause of 
this cause; [but must rest contented with it as the ul- 
timate principle, which we can assign, of all our con- 
clusions from experienced It is sufficient satisfaction, 
that we can go so far, without repining at the narrow- 
ness of our faculties because they will carry us no far- 
ther. And it is certain we here advance a very intel- 
ligible proposition at least, if not a true one, when we 
assert that, after the constant conjunction of two ob- 
jects — heat and flame, for instance, weight and solidity 
— we are determined by custom alone to expect the 
one from the appearance of the other. This hypothesis 
seems even the only one which explains the difficulty, 
why we draw, from a thousand instances, an inference 
which we are not able to draw from one instance, th^t 
is, in no respect, different from them. Reason is incap- 
able of any such variation. The conclusions which it 



44 AN ENQUIRY CONCERNING 

draws from considering one circle are the same which 
it would form upon surveying all the circles in the 
universe. But no man, having seen only one body 
move after being impelled by another, could infer that 
every other body will move after a like impulse. Al 
inferences from experience, therefore, are effects of 
custom, not of reasoning. 1 

1 Nothing is more useful than for writers, even, on moral, political, or 
physical subjects, to distinguish between reason and experience, and to sup- 
pose, that these species of argumentation are entirely different from each 
other. The former are taken for the mere result of our intellectual faculties, 
which, by considering a priori the nature of things, and examining the effects, 
that must follow from their operation, establish particular principles of sci- 
ence a; d rhilosophy. The latter are supposed to be derived entirely from 
sense and observation, by which we learn what has actually resulted from the 
operation of particular objects, and are thence able to infer, what will, for 
the future, result from them. Thus, for instance, the limitations and restraints 
of civil government, and a legal constitution, may be defended, either from 
reason, which reflecting on the great frailty and corruption of human nature, 
teaches, that no man can safely be trusted with unlimited authority \ or from 
experience and history, which inform us of the enormous abuses, that ambi- 
tion, in every age and country, has been found to make of so imprudent a 
co fidence. 

The same distinction between reason and experience is maintained in all 
our deliberations concerning the conduct of life ; while the experience! .1 
statesman, general, physician, or merchant is trusted and followed ; and tha 
unpractised novice, with whatever natural talents endowed, neglected and 
despised. Though it be allowed, that reason may form very plausible 
conjectures with regard to the consequences of such a particular conduct in 
such particular circumstances; it is still supposed imperfect, without the 
assistance of experience, which is alone able to give stability and certainty 
to the maxims, derived from study and reflection. 

But notwithstanding that this distinction be thus universally received, 
both in the active speculative scenes of life, I shall not scruple to pronounce, 
that it is, at bottom, erroneous, at least, superficial 

If we examine those arguments, which, in any of the sciences above men- 
tioned, are supposed to be the mere effects of reasoning and reflection, they 
wi'.l be found to terminate, at last, in some general principle or conclusion, 
for which we can assign no reason but observation and experience. The only 
difference between them and those maxims, which are vulgarly esteemed the 
resu'.t of pure experience, is, that the former cannot be established without 
some process of thought, and some reflection on what we have observed, in 
order to distinguish its circumstances, and trace its consequences : Whereas 
in the latter, the experienced event is exactly and fully familiar to that which 
we infer as the result of any particular situation. The history of a Tiberius 
or a Nero makes us dread a like tyranny, were our monarchs freed from the 
restraints of laws and senates: But the observation of any fraud or cruelty 



HUMAN UNDERSTANDING. 45 

Custom, then, is the great guide of human life. It 
is that principle alone which renders our experience 
useful to us, and makes us expect, for the future, a 
similar train of events with those which have appeared 
in the past. Without the influence of custom, we 
should be entirely ignorant of every matter of fact be- 
yond what is immediately present to the memory and 
senses. We should never know how to adjust means 
to ends, or to employ our natural powers in the pro- 
duction of any effect. There would be an end at once 
of all action, as well as of the chief part of speculation. 

But here it may be proper to remark, that though 
our conclusions from experience carry us beyond our 
memory and senses, and assure us of matters of fact 
which happened in the most distant places and most 
remote ages, yet some fact must always be present to 
the senses or memory, from which we may first pro- 
ceed in drawing these conclusions. A man, who should 
find in a desert country the remains of pompous build- 
ings, would conclude that the country had, in ancient 

in private life is sufficient, with the aid of a little thought, to give us the same 
apprehension; while it serves as an instance of the general corruption of 
human nature, and shows us the danger which we must incur by reposing an 
( ntire confidence in mankind. In both cases, it is experience which is ulti- 
mately tha foundation of our inference and conclusion. 

There is no man so young and unexperienced, as not to have formed, from 
observation, many general and just maxims concerning human affairs and the 
Conduct of life; but it must be confessed, that, when a man comes to put 
these in practice, he will be extremely liable to error, till time and farther 
experience both enlarge these maxims, and teach him their proper use and 
application. In every situation or incident, there are many particular an:l 
seemingly minute circumstances, which the man of greatest talent is, at first, 
apt to overlook, though on them the justness of his conclusions, and conse 
quently the prudence of his conduct, entirely depend. Not to mention, that, 
to a young beginner, the general observations and maxims occur not always 
on the proper occasions, nor can be immediately applied with due calmness 
and distinction. The truth is, an unexperienced reasoner could be no reat 
soner at ail, were he absolutely unexperienced; and when we assign tha 
character to any one, we mean it only in a comparative sense, and suppose 
him possessed of experience, in a smaller and more imperfect degree. 



/ 



46 AN ENQ UIR Y CONCERNING 

times, been cultivated by civilized inhabitants ; but 
did nothing of this nature occur to him, he could never 
form such an inference. We learn the events of former 
ages from history; but then we must peruse the vol- 
umes in which this instruction is contained, and thence 
carry up our inferences from one testimony to another, 
till we arrive at the eyewitnesses and spectators of 
these distant events. In a word, if we proceed not 
upon some fact, present to the memory or senses, our 
reasonings would be merely hypothetical; and how- 
ever the particular links might be connected with each 
other, the whole chain of inferences would have noth- 
ing to support it, nor could we ever, by its means, ar- 
rive at the knowledge of any real existence. If I ask 
why you believe any particular matter of fact, which 
you relate, you must tell me some reason ; and this 
reason will be some other fact, connected with it. 
But as you cannot proceed after this manner, in infini- 
tum, you must at last terminate in some fact, which is 
present to your memory or senses; or must allow that 
your belief is entirely without foundation. 

What, then, is the conclusion of the whole matter ? 
A simple one; though, it must be confessed, pretty 
remote from the common theories of philosophy. All 
belief of matter of fact or real existence is derived 
merely from some object, present to the memory or 
senses, and a customary conjunction between that and 
some other object. Or in other words; having found 
in many instances, that any two kinds of objects — 
flame and heat, snow and cold — have always been con- 
joined together ; if flame or snow be presented anew 
to the senses, the mind is carried by custom to expect 
heat or cold, and to believe that such a quality does 
exist, and will discover itself upon a nearer approach. 



HUMAN UNDERSTANDING. 47 

This belief is the necessary result of placing the mind 
in such circumstances. It is an operation of the soul, 
when we are so situated, as unavoidable as to feel the 
passion of love, when we receive benefits ; or hatred, 
when we meet w T ith injuries. All these operations are 
a species of natural instincts, which no reasoning or 
process of the thought and understanding is able either 
to produce or to prevent. 

At this point, it would be very allowable for us to 
stop our philosophical researches. In most questions 
we can never make a single step farther ; and in all 
questions we must terminate here at last, after our most 
restless and curious enquiries. But still our curiosity 
will be pardonable, perhaps commendable, if it carry 
us on to still farther researches, and make us examine 
more accurately the nature of this belief, and of the 
customary conjunction, whence it is derived. By this 
means we may meet with some explications and anal- 
ogies that will give satisfaction ; at lea t to such as 
love the abstract sciences, and can be entertained with 
speculations, which, however accurate, may still retain 
a degree of doubt and uncertainty. As to readers of 
a different taste ; the remaining part of this section is 
not calculated for them, and the following enquiries 
may well be understood, though it be neglected. 

Part II. 

Nothing is more free than the imagination of man ; 
and though it cannot exceed that original stock of 
ideas furnished by the internal and external senses, it 
has unlimited power of mixing, compounding, separ- 
ating, and dividing these ideas, in all the varieties of 
fiction and vision. It can feign a train of events, with 
all the appearance of reality, ascribe to them a partic- 



48 AN ENQ UIR Y CONCERNING 

ular time and place, conceive them as existent, and 
paint them out to itself with every circumstance, that 
belongs to any historical fact, which it believes with 
the greatest certainty. Wherein, therefore, consists 
the difference between such a fiction and belief? It 
lies not merely in any peculiar idea, which is annexed 
to such a conception as commands our assent, and 
which is wanting to every known fiction. \For as the 
mind has authority over all its ideas J it cou'd volun- 
tarily annex this particular idea to any fiction, and con- 
sequently be able to believe whatever it pleases ; con- 
trary to what we find by daily experience. We can, in 
our conception, join the head of a man to the body of 
a horse ; but it is not in our power to believe that such 
an animal has ever really existed. 

It follows, therefore, that the difference between 
Hction and belief lies in some sentiment or feeling, 
which is annexed to the latter, not to the former, and 
which depends not on the will, nor can be commanded 
at pleasure. It must be excited by nature, like all 
other sentiments; and must arise from the particular 
situation, in which the mind is placed at any particu- 
lar juncture. Whenever any object is presented to the 
memory or senses, it immediately, by the force of cus- 
tom, carries the imagination to conceive that object, 
which is usually conjoined to it ; and this conception 
is attended with a feeling or sentiment, different from 
the loose reveries of the fancy. In this consists the 
whole nature of belief. For as there is no matter of 
fact which we believe so firmly that we cannot con- 
ceive the contrary, there would be no difference be- 
tween the conception assented to and that which is 
rejected, were it not for some sentiment which dis- 
tinguishes the one from the other. If I see a billiard- 



HUMAN UNDERSTANDING. 49 

ball moving towards another, on a smooth table, I can 
easily conceive it to stop upon contact. This concep- 
tion implies no contradiction; but still it feels very 
differently from that conception by which I represent 
to myself the impulse and the communication of mo- 
tion from one ball to another. 

Were we to attempt a definition of this sentiment, 
we should, perhaps, find it a very difficult, if not an 
impossible task ; in the same manner as if we should 
endeavour to define the feeling of cold or passion of 
anger, to a creature who never had any experience of 
these sentiments. Belief is the true and proper name 
of this feeling; and no one is ever at a loss to know 
the meaning of that term ; because every man is every 
moment conscious of the sentiment represented by it. 
It may not, however, be improper to attempt a descrip- 
tion of this sentiment ; in hopes we may, by that means, 
arrive at some analogies, which may afford a more 
perfect explication of it. I say, then, that belief is 
nothing but a more vivid, lively, forcible, firm, steady 
conception of an object, than what the imagination 
alone is ever able to attain. This variety of terms, 
which may seem so unphilosophical, is intended only 
to express that act of the mind, which renders realities, 
or what is taken for such, more present to us than fic~ 
tions, causes them to weigh more in the thought, and 
gives them a superior influence on the passions and 
imagination. Provided we agree about the thing, it is 
needless to dispute about the terms. The imagination 
has the command over all its ideas, and can join and 
mix and vary them, in all the ways possible. It may 
conceive fictitious objects with*all the circumstances 
of place and time. It may set them, in a manner, be- 
fore our eyes, in their true colours, just as they might 



50 AN ENQUIRY CONCERNING 

have existed. But as it is impossible that this faculty 
of imagination can ever, of itself, reach belief, it is 
evident that belief consists not in the peculiar nature 
or order of ideas, but in the manner of their concep- 
tion, and in their feeling to the mind. I confess, that 
it is impossible perfectly to explain this feeling or 
manner of conception. We may make use of words 
which express something near it. But its true and 
proper name, as we observed before, is belief; which 
is a term that every one sufficiently understands in 
common life. And in philosophy, we can go no farther 
than assert, that belief is something felt by the mind, 
which distinguishes the ideas of the judgement from the 
fictions of the imagination. It gives them more weight 
and influence ; makes them appear of greater impor- 
tance ; enforces them in the mind ; and renders them 
the governing principle of our actions. I hear at pres- 
ent, for instance, a person's voice, with whom I am 
acquainted ; and the sound comes as from the next 
room. This impression of my senses immediately con- 
veys my thought to the person, together with all the 
surrounding objects. I paint them out to myself as 
existing at present, with the same qualities and rela- 
tions, of which I formerly knew them possessed. 
These ideas take faster hold of my mind than ideas of 
an enchanted castle. They are very different to the 
feeling, and have a much greater influence of every 
kind, either to give pleasure or pain, joy or sorrow. 
Let us, then, take in the whole compass of this 
doctrine, and allow, that the sentiment of belief is 
nothing but a conception more intense and steady than 
what attends the mere fictions of the imagination, and 
that this manner of conception arises from a customary 
conjunction of the object with something present to 



HUMAN UNDERSTANDING. 51 

the memory or senses: I believe that it will not be 
difficult, upon these suppositions, to find other opera- 
tions of the mind analogous to it, and to trace up these 
phenomena to principles still more general. 

We have already observed that nature has estab- 
lished connexions among particular ideas, and that no 
sooner one idea occurs to our thoughts than it intro- 
duces its correlative, and carries our attention towards 
it, by a gentle and insensible movement. These prin- 
ciples of connexion or association we have reduced to 
three, namely, Resemblance, Contiguity and Causation-, 
which are the only bonds that unite our thoughts' to- 
gether, and beget that regular train of reflection or 
discourse, which, in a greater or less degree, takes 
place among mankind. Now here arises a question, 
on which the solution of the present difficulty will de- 
pend. Does it happen, in all these relations, that, 
when one of the objects is presented to the senses or 
memory, the mind is not only carried to the concep- 
tion of the correlative, but reaches a steadier and 
stronger conception of it than what otherwise it would 
have been able to attain ? This seems to be the case 
with that belief which arises from the relation of cause 
and effect. And if the case be the same with the other 
relations or principles of associations, this may be es- 
tablished as a general law, which takes place in all the 
operations of the mind. 

We may, therefore, observe, as the first experiment 
to our present purpose, that, upon the appearance of 
the picture of an absent friend, our idea of him is evi- 
dently enlivened by the resemblance, and that every 
passion, which that idea occasions, whether of joy or 
sorrow, acquires new force and vigour. In producing 
this effect, there concur both a relation and a present 



52 AN ENQ UIR Y CONCERNING 

impression. Where the picture bears him no resem- 
blance, at least was not intended for him, it never so 
much as conveys our thought to him : And where it 
is absent, as well as the person, though the mind m ly 
pass from the thought of the one to that of the other, 
it feels its idea to be rather weakened than enlivened 
by that transition. We take a pleasure in viewing the 
picture of a friend, when it is set before us ; but when 
it is removed, rather choose to consider him directly 
than by reflection in an image, which is equally distant 
and obscure. 

The ceremonies of the Roman Catholic religion 
may be considered as instances of the same nature. 
The devotees of that superstition usually plead in ex- 
cuse for the mummeries, with which they were up- 
braided, that they feel the good effect of those exter- 
nal motions, and postures, and actions, in enlivening 
their devotion and quickening their fervour, which 
otherwise would decay, if directed entirely to distant 
and immaterial objects. We shadow out the objects 
of our faith, say they, in sensible types and images, 
and render them more present to us by the immediate 
presence of these types, than it is possible for us to do 
merely by an intellectual view and contemplation. 
Sensible objects have always a greater influence on the 
fancy than any other ; and this influence they readily 
convey to those ideas to which they are related, and 
which they resemble. I shall only infer from these 
practices, and this reasoning, that the effect of resem- 
blance in enlivening the ideas is very common ; and 
as in every case a resemblance and a present impres- 
sion must concur, we are abundantly supplied with 
experiments to prove the reality of the foregoing prin- 
ciple. 



HUMAN- UNDERSTANDING. 53 

We may add force to these experiments by others 
of a different kind, in considering the effects of contig- 
uity as well as of rese?nblance. It is certain that dis- 
tance diminishes the force of every idea, and that, 
upon our approach to any object ; though it does not 
discover itself to our senses ; it operates upon the mind 
with an influence, which imitates an immediate im- 
pression. The thinking on any object readily trans- 
ports the mind to what is contiguous ; but it is only 
the actual presence of an object, that transports it with 
a superior vivacity. When I am a few miles from 
home, whatever relates to it touches me more nearly 
than when I am two hundred leagues distant ; though 
even at that distance the reflecting on anything in the 
neighbourhood of my friends or family naturally pro- 
duces an idea of them. But as in this latter case, both 
the objects of the mind are ideas; notwithstanding 
there is an easy transition between them ; that transi- 
tion alone is not able to give a superior vivacity to any 
of the ideas, for want of some immediate impression. 1 

No one can doubt but causation has the same in- 
fluence as the other two relations of resemblance and 
contiguity. Superstitious people are fond of the rel- 
iques of saints and holy men, for the same reason, that 
they seek after types or images, in order to enliven 

1 * Naturane nobis, inquit, datum dicam, an errore quodam, ut, cum ea 
loca videamus, in quibus inemoria dignos viros acceperimus multum esse 
versatos, magis moveamur, quam siquando eorum ipsorum aut facta audiamus 
aut scriptum aliquod legamus ? Velut ego nunc moveor. Venit enim mini 
Plato in mentem, quern accepimus primum hie disputare solitum: cuius etiam 
illi hortuli propinqui non memoriam solum mihi afferunt, sed ipsum videntur 
in conspectu meo hie ponere. Hie Speusippus, hie Xenocrates, hie eius 
auditor Polemo ; cuius ipsa ilia sessio fuit, quam videmus. Equidem etiam 
curiam nostram, Hostiliam dico, non hanc novam, quae mihi minor esse 
videtur postquam est maior, solebam intuens, Scipionem, Catonem, Laelium; 
nostrum vero in primis avum cogitare. Tanta vis admonitionis est in locis; 
ut non sine causa ex his memoriae deducta sit disciplina.' 

Cicero de Finibus. Lib. v. 



54 AN ENQ UIR V CONCERNING 

their devotion, and give them a more intimate and 
strong conception of those exemplary lives, which they 
desire to imitate. Now it is evident, that one of the 
best reliques, which a devotee could procure, would 
be the handy v/ork of a saint; and if his cloaths and 
furniture are ever to be considered in this light, it is 
because they were once at his disposal, and were moved 
and affected by him ; in which respect they are to be 
considered as imperfect effects, and as connected with 
him by a shorter chain of consequences than any of 
those, by which we learn the reality of his existence. 

Suppose, that the son of a friend, who had been 
long dead or absent, were presented to us; it is evi- 
dent, that this object would instantly revive its corre- 
lative idea, and recall to our thoughts all past intima- 
cies and familiarities, in more lively colours than they 
would otherwise have appeared to us. This is another 
phaenomenon, which seems to prove the principle 
above mentioned. 

We may observe, that, in these phaenomena, the 
belief of the correlative object is always presupposed ; 
without which the relation could have no effect. The 
influence of the picture supposes, that we believe our 
friend to have once existed. Contiguity to home can 
never excite our ideas of home, unless we believe that 
it really exists. Now I assert, that this belief, where 
it reaches beyond the memory or senses, is of a simi- 
lar nature, and arises from similar causes, with th< 
transition of thought and vivacity of conception here 
explained. When I throw a piece of dry wood into 
fire, my mind is immediately carried to conceive, thai 
it augments, not extinguishes the flame. This transi- 
tion of thought from the cause to the effect proceed; 
not from reason. It derives its origin altogether from 



HUMAN UNDERSTANDING. 55 

custom and experience. And as it first begins from an 
object, present to the senses, it renders the idea or con- 
ception of flame more strong and lively than any loose, 
floating reverie of the imagination. That idea arises 
immediately. The thought moves instantly towards 
it, and conveys to it all that force of conception, which 
is derived from the impression present to the senses. 
When a sword is levelled at my breast, does not the 
idea of wound and pain strike me more strongly, than 
when a glass of wine is presented to me, even though 
by accident this idea should occur after the appearance 
of the latter object ? But what is there in this whole 
matter to cause such a strong conception, except only 
a present object and a customary transition to the idea 
of another object, which we have been accustomed to 
conjoin with the former ? This is the whole operation 
of the mind, in all our conclusions concerning matter 
of fact and existence ; and it is a satisfaction to find 
some analogies, by which it may be explained. The 
transition from a present object does in all cases give 
strength and solidity to the related idea. 

Here, then, is a kind of pre-established harmony 
between the course of nature and the succession of 
our ideas ; and though the powers and forces, by which ; 
the former is governed, be wholly unknown to us; yet 
our thoughts and conceptions have still, we find, gone | 
on in the same train with the other works of nature. 
Custom is that principle, by which this correspondence 
has been effected ; so necessary to the subsistence of 
our species, and the regulation of our conduct, in every 
circumstance and occurrence of human life. Had not i 
the presence of an object, instantly excited the idea 
of those objects, commonly conjoined with it, all our 
knowledge must have been limited to the narrow sphere 



56 AN EJS Q I ■ IR Y CO NCERNING 

of our memory and senses ; and we should never have 
been able to adjust means to ends, or employ our nat- 
ural powers, either to the producing of good, or avoid- 
ing of evil. Those, who delight in the discovery and 
contemplation of final causes, have here ample subject 
to employ their wonder and admiration. 

I shall add, for a further confirmation of the fore- 
going theory, that, as this operation of the mind, by 
which we infer like effects from like causes, and vice 
versa, is so essential to the subsistence of all human 
creatures, it is not probable, that it could be trusted to 
the fallacious deductions of our reason, which is slow 
in its operations ; appears not, in any degree, during 
the first years of infancy ; and at best is, in every age 
and period of human life, extremely liable to error and 
mistake. It is more conformable to the ordinary wis- 
dom of nature to secure so necessary an act of the 
mind, by some instinct or mechanical tendency, which 
may be infallible in its operations, may discover itself 
at the first appearance of life and thought, and may 
be independent of all the laboured deductions of the 
understanding. As nature has taught us the use of 
our limbs, without giving us the knowledge of the 
muscles and nerves, by which they are actuated; so 
has she implanted in us an instinct, which carries for- 
ward the thought in a correspondent course to that 
which she has established among external objects ; 
though we are ignorant of those powers and forces, on 
which this regular course and succession of objects 
totally depends. 



SECTION VI. 

OF PROBABILITY. 1 

THOUGH there be no such thing as Chance in the 
world; our ignorance of the real cause of any 
event has the same influence on the understanding, 
and begets a like species of belief or opinion. 

There is certainly a probability, which arises from 
a superiority of chances on any side ; and according 
as this superiority encreases, and surpasses the oppo- 
site chances, the probability receives a proportionable 
encrease, and begets still a higher degree of belief or 
assent to that side, in which we discover the superior- 
ity. If a dye were marked with one figure or number 
of spots on four sides, and with another figure or num- 
ber of spots on the two remaining sides, it would be 
more probable, that the former would turn up than 
the latter ; though, if it had a thousand sides marked 
in the same manner, and only one side different, the 
probability would be much higher, and our belief or 
expectation of the event more steady and secure. This 
process of the thought or reasoning may seem trivial 
and obvious ; but to those who consider it more nar- 



1 Mr. Locke divides all arguments into demonstrative and probable. In 
this view, we must say, that it is only probable all men must die, or that the 
sun will rise to-morrow. But to conform our language more to common use, 
we ought to divide arguments into demonstrations, proofs, and probabilities. 
By proofs meaning such arguments from experience as leave nq room for 
doubt or opposition. 



58 AN ENQ UIR Y CONCERNING 

rowly, it may, perhaps, afford matter for curious spec- 
ulation. 

It seems evident, that, when the mind looks for- 
ward to discover the event, which may result from the 
throw of such a dye, it considers the turning up of 
each particular side as alike probable ; and this is the 
very nature of chance, to render all the particular 
events, comprehended in it, entirely equal. But find- 
ing a greater number of sides concur in the one event 
than in the other, the mind is carried more frequently 
to that event, and meets it oftener, in revolving the 
various possibilities or chances, on which the ultimate 
result depends. This concurrence of several views in 
one particular event begets immediately, by an inex- 
plicable contrivance of nature, the sentiment of belief, 
and gives that event the advantage over its antagonist, 
which is supported by a smaller number of views, and 
recurs less frequently to the mind. If we allow, that 
belief is nothing but a firmer and stronger conception 
of an object than what attends the mere fictions of the 
imagination, this operation may, perhaps, in some 
measure, be accounted for. The concurrence of these 
several views or glimpses imprints the idea more 
strongly on the imagination; gives it superior force 
and vigour ; renders its influence on the passions and 
affections more sensible ; and in a word, begets that 
reliance or security, which constitutes the nature of 
belief and opinion. 

The case is the same with the probability of causes, 
as with that of chance. There are some causes, which 
are entirely uniform and constant in producing a par- 
ticular effect ; an*d no instance has ever yet been found 
of any failure or irregularity in their operation. Fire 
has always burned, and water suffocated every human 






HUMAN UNDERSTANDING. 59 

creature : The production of motion by impulse and 
gravity is an universal law, which has hitherto admit- 
ted of no exception. But there are other causes 
which have been found more irregular and uncertain; 
nor has rhubarb always proved a purge, or opium a 
soporific to every one, who has taken these medicines. 
It is true, when any cause fails of producing its usual 
effect, philosophers ascribe not this to any irregularity 
'n nature; but suppose, that some secret causes, in the 
particular structure of parts, have prevented the op- 
eration. Our reasonings, however, and conclusions 
concerning the event are the same as if this principle 
had no place. Being determined by custom to transfer 
the past to the future, in all our inferences ; where 
the past has been entirely regular and uniform, we ex- 
pect the event with the greatest assurance, and leave 
no room for any contrary supposition. But where 
different effects have been found to follow from 
causes, which are to appearance exactly similar, all 
these various effects must occur to the mind in trans- 
ferring the past to the future, and enter into our con- 
sideration, when we determine the probability of the 
event. Though we give the preference to that which 
has been found most usual, and believe that this effect 
will exist, we must not overlook the other effects, but 
must assign to each of them a particular weight and 
authority, in proportion as we have found it to be more 
or less frequent. It is more probable, in almost every 
country of Europe, that there will be frost sometime 
in January, than that the weather will continue open 
throughout the whole month ; though this probability 
varies according to the different climates, and ap- 
proaches to a certainty in the more northern kingdoms. 
Here then it seems evident, that, when we transfer the 



60 A N ENQ UIR Y CONCERNING 

past to the future, in order to determine the effect, 
which will result from any cause, we transfer all the 
different events, in the same proportion as they have 
appeared in the past, and conceive one to have existed 
a hundred times, for instance, another ten times, and 
another once. As a great number of views do here 
concur in one event, they fortify and confirm it to the 
imagination, beget that sentiment which we call belief, 
and give its object the preference above the contrary 
event, which is not supported by an equal number of 
experiments, and recurs not so frequently to the 
thought in transferring the past to the future. Let 
any one try to account for this operation of the mind 
upon any of the received systems of philosophy, and 
he will be sensible of the difficulty. For my part, I 
shall think it sufficient, if the present hints excite the 
curiosity of philosophers, and make them sensible 
how defective all common theories are in treating of 
such curious and such sublime subjects. 



SECTION VII. 

OF THE IDEA OF NECESSARY CONNEXION. 
Part I. 

THE great advantage of the mathematical sciences 
above the moral consists in this, that the ideas of 
the former, being sensible, are always clear and deter- 
minate, the smallest distinction between them is im- 
mediately perceptible, and the same terms are still 
expressive of the same ideas, without ambiguity or 
variation. An oval is never mistaken for a circle, nor 
an hyperbola for an ellipsis. The isosceles and scale- 
num are distinguished by boundaries more exact than 
vice and virtue, right and wrong. If any term be de- 
fined in geometry, the mind readily, of itself, substi- 
tutes, on all occasions, the definition for the term de- 
fined : Or even when no definition is employed, the 
object itself may be presented to the senses, and by 
that means be steadily and clearly apprehended. But 
the finer sentiments of the mind, the operations of the 
understandiug, the various agitations of the passions, 
though really in themselves distinct, easily escape us, 
when surveyed by reflection ; nor is it in our power to 
recall the original object, as often as we have occasion 
to contemplate it. Ambiguity, by this means, is grad- 
ually introduced into our reasonings : Similar objects 
are readily taken to be the same: And the conclusion 
becomes at last very wide of the premises, 



62 AN ENQUIRY CONCERNING 

One may safely, however, affirm, that, if we con- 
sider these sciences in a proper light, their advantages 
and disadvantages nearly compensate each other, and 
reduce both of them to a state of equality. If the 
mind, with greater facility, retains the ideas of geom- 
etry clear and determinate, it must carry on a much 
longer and more intricate chain of reasoning, and 
compare ideas much wider of each other, in order to 
reach the abstruser truths of that science. And if 
moral ideas are apt, without extreme care, to fall into 
obscurity and confusion, the inferences are always 
much shorter in these disquisitions, and the interme- 
diate steps, which lead to the conclusion, much fewer 
than in the sciences which treat of quantity and num- 
ber. In reality, there is scarcely a proposition in 
Euclid so simple, as not to consist of more parts, than 
are to be found in any moral reasoning which runs not 
into chimera and conceit. Where we trace the prin- 
ciples of the human mind through a few steps, we may 
be very well satisfied with our progress ; considering 
how soon nature throws a bar to all our enquiries con- 
cerning causes, and reduces us to an acknowledgment 
of our ignorance. The chief obstacle, therefore, to 
our improvement in the moral or metaphysical sci- 
ences is the obscurity of the ideas, and ambiguity of 
the terms. The principal difficulty in the mathematics 
is the length of inferences and compass of thought, 
requisite to the forming of any conclusion. And, per- 
haps, our progress in natural philosophy is chiefly re- 
tarded by the want of proper experiments and phae- 
nomena, which are often discovered by chance, and 
cannot always be found, when requisite, even by the 
most diligent and prudent enquiry. As moral philos- 
ophy seems hitherto to have received less improve- 



HUMAN UNDERSTANDING. 63 

ment than either geometry or physics, we may con- 
clude, that, if there be any difference in this respect 
among these sciences, the difficulties, which obstruct 
the progress of the former, require superior care and 
capacity to be surmounted. 

There are no ideas, which occur in metaphysics, 
more obscure and uncertain, than those of power, force, 
energy or necessary connexion, of which it is every mom- 
ent necessary for us to treat in all our disquisitions. 
We shall, therefore, endeavour, in this section, to fix, 
if possible, the precise meaning of these terms, and 
thereby remove some part of that obscurity, which is 
so much complained of in this species of philosophy. 

It seems a proposition, which will not admit of 
much dispute, that all our ideas are nothing but copies 
of our impressions, or, in other words, that it is impos- 
sible for us to think of any thing, which we have not ante- 
cedently/^//, either by our external or internal senses. 
I have endeavoured 1 to explain and prove this propo- 
sition, and have expressed my hopes, that, by a proper 
application of it, men may reach a greater clearness 
and precision in philosophical reasonings, than what 
they have hitherto been able to attain. Complex ideas 
may, perhaps, be well known by definition, which is 
nothing but an enumeration of those parts or simple 
ideas, that compose them. But when we have pushed 
up definitions to the most simple ideas, and find still 
some ambiguity and obscurity ; what resource are we 
then possessed of ? By what invention can we throw 
light upon these ideas, and render them altogether 
precise and determinate to our intellectual view? 
Produce the impressions or original sentiments, from 
which the ideas are copied. These impressions are al 

1 Section II. 



64 AN ENQUIR Y CONCERNING 

strong and sensible. They admit not of ambiguity. 
They are not only placed in a full light themselves, 
but may throw light on their correspondent ideas, 
which lie in obscurity. And by this means, we may, 
perhaps, attain a new microscope or species of optics, 
by which, in the moral sciences, the most minute, and 
most simple ideas may be so enlarged as to fall readily 
under our apprehension, and be equally known with 
the grossest and most sensible ideas, that can be the 
object of our enquiry. 

To be fully acquainted, therefore, with the idea of 
power or necessary connexion, let us examine its im- 
pression ; and in order to find the impression with 
greater certainty, let us search for it in all the sources, 
from which it may possibly be derived. 

When we look about us towards external objects, 
and consider the operation of causes, we are never 
able, in a single instance, to discover any power or 
necessary connexion ; any quality, which binds the 
effect to the cause, and renders the one an infallible 
consequence of the other. We only find, that the one 
does actually, in fact, follow the other. The impulse 
of one billiard-ball is attended with motion in the sec- 
ond. This is the whole that appears to the outward 
senses. The mind feels no sentiment or inward im- 
pression from this succession of objects : Consequently 
there is not, in any single, particular instance of cause 
and effect, any thing which can suggest the idea of 
power or necessary connexion. 

From the first appearance of an object, we never 
can conjecture what effect will result from it. But 
were the power or energy of any cause discoverable 
by the mind, we could foresee the effect, even without 
experience; and might, at first, pronounce with cer* 



HUMAN UNDERSTANDING, 65 

tainty concerning it, by mere dint of thought and rea- 
soning. 

In reality, there is no part of matter, that does 
ever, by its sensible qualities, discover any power or 
energy, or give us ground to imagine, that it could 
produce any thing, or be followed by any other object, 
which we could denominate its effect. Solidity, exten- 
sion, motion ; these qualities are all complete in them- 
selves, and never point out any other event which may 
result from them. The scenes of the universe are con- 
tinually shifting, and one object follows another in an 
uninterrupted succession ; but the power of force, 
which actuates the whole machine, is entirely con- 
cealed from us, and never discovers itself in any of the 
sensible qualities of body. We know, that, in fact, 
heat is a constant attendant of flame ; but what is the 
connexion between them, we have no room so much 
as to conjecture or imagine. It is impossible, there- 
fore, that the idea of power can be derived from the 
contemplation of bodies, in single instances of their 
operation ; because nobodies ever discover any power, 
which can be the original of this idea. 1 

Since, therefore, external objects as they appear to 
the senses, give us no idea of power or necessary con- 
nexion, by their operation in particular instances, let 
us see, whether this idea be derived from reflexion on 
the operations of our own minds, and be copied from 
any internal impression. It may be said, that we are 
every moment conscious of internal power; while we 



1 Mr. Locke, in his chapter of power, says, that, finding from experience, 
that there are several new productions in matter, and concluding that there 
must somewhere be a power capable of producing them, we arrive at last by 
this reasoning at the idea of power. But no reasoning can ever give us a new, 
original, simple idea ; as this philosopher himself confesses. This, therefore, 
can never be the origin of that idea. 



66 AN ENQ UIR V CONCERNING 

feel, that, by the simple command of our will, we can 
move the organs of our body, or direct the faculties of 
our mind. An act of volition produces motion in our 
limbs, or raises a new idea in our imagination. This 
influence of the will we know by consciousness. Hence 
we acquire the idea of power or energy; and are cer- 
tain, that we ourselves and all other intelligent beings 
are possessed of power. This idea, then, is an idea 
of reflection, since it arises from reflecting on the op- 
erations of our own mind, and on the command which 
is exercised by will, both over the organs of the body 
and faculties of the soul. 

We shall proceed to examine this pretension ; and 
first with regard to the influence of volition over the 
organs of the body. This influence, we may observe, 
is a fact, which, like all other natural events, can be 
known only by experience, and can never be foreseen 
from any apparent energy or power in the cause, which 
connects it with the effect, and renders the one an in- 
fallible consequence of the other. The motion of our 
body follows upon the command of our will. Of this 
we are every moment conscious. But the means, by 
which this is effected ; the energy, by which the will 
performs so extraordinary an operation ; of this we are 
so far from being immediately conscious, that it must 
for ever escape our most diligent enquiry. 

For first) is there any principle in all nature more 
mysterious than the union of soul with body; by which 
a supposed spiritual substance acquires such an influ- 
ence over a material one, that the most refined thought 
is able to actuate the grossest matter ? Were we em- 
powered, by a secret wish, to remove mountains, or 
control the planets in their orbit ; this extensive au- 
thority would not be more extraordinary, nor more 



HUMAN UNDERSTANDING. 67 

beyond our comprehension. But if by consciousness 
we perceived any power or energy in the will, we must 
know this power; we must know its connexion with 
the effect ; we must know the secret union of soul and 
body, and the nature of both these substances; by 
which the one is able to operate, in so many instances, 
upon the other. 

Secondly, We are not able to move all the organs of 
the body with a like authority ; though we cannot as- 
sign any reason besides experience, for so remarkable 
a difference between one and the other. Why has the 
will an influence over the tongue and fingers, not over 
the heart and liver ? This question would never em- 
barrass us, were we conscious of a power in the former 
case, not in the latter. We should then perceive, in- 
dependent of experience, why the authority of will 
over the organs of the body is circumscribed within 
such particular limits. Being in that case fully ac- 
quainted with the power or force, by which it operates, 
we should also know, why its influence reaches pre- 
cisely to such boundaries, and no farther. 

A man, suddenly struck with palsy in the leg or 
arm, or who had newly lost those members, frequently 
endeavours, at first to move them, and employ them in 
their usual offices. Here he is as much conscious of 
power to command such limbs, as a man in perfect 
health is conscious of power to actuate any member 
which remains in its natural state and condition. But 
consciousness never deceives. Consequently, neither 
in the one case nor in the other, are we ever conscious 
of any power. We learn the influence of our will from 
experience alone. And experience only teaches us, 
how one event constantly follows another ; without 



68 AN ENQUIRY CONCERNING 

instructing us in the secret connexion, which binds 
them together, and renders them inseparable. 

Thirdly, We learn from anatomy, that the immedi- 
ate object of power in voluntary motion, is not the 
member itself which is moved, but certain muscles, 
and nerves, and animal spirits, and, perhaps, some- 
thing still more minute and more unknown, through 
which the motion is successfully propagated, ere it 
reach the member itself whose motion is the immediate 
object of volition. Can there be a more certain proof 
that the power, by which this whole operation is per- 
formed, so far from being directly and fully known by 
an inward sentiment or consciousness, is, to the last 
degree, mysterious and unintelligible ? Here the mind 
wills a certain event : Immediately another event, un- 
known to ourselves, and totally different from the one 
intended, is produced: This event produces another, 
equally unknown : Till at last, through a long succes- 
sion, the desired event is produced. But if the original 
power were felt, it must be known : Were it known, 
its effect also must be known; since all power is rela- 
tive to its effect. And vice versa, if the effect be not 
known, the power cannot be known nor felt. How in- 
deed can we be conscious of a power to move our limbs, 
when we have no such power; but only that to move 
certain animal spirits, which, though they produce at 
last the motion of our limbs, yet operate in such a 
manner as is wholly beyond our comprehension ? 

We may, therefore, conclude from the whole, I 
hope, without any temerity, though with assurance; 
that our idea of power is not copied from any senti- 
ment or consciousness of power within ourselves, when 
we give rise to animal motion, or apply our limbs, to 
their proper use and office. That their motion follows 



HUMAN UNDERSTANDING. 69 

the command of the will is a matter of common expe- 
rience, like other natural events : But the power or 
energy by which this is effected, like that in other 
natural events, is unknown and inconceivable. 1 

Shall we then assert, that we are conscious of a 
power or energy in our own minds, when, by an act 
or command of our w r ill, we raise up a new idea, fix 
the mind to the contemplation of it, turn it on all sides, 
and at last dismiss it for some other idea, when we 
think that we have surveyed it with sufficient accuracy? 
I believe the same arguments will prove, that even 
this command of the will gives us no real idea of force 
or energy. 

First, It must be allowed, that, when we know a 
power, we know that very circumstance in the cause, 
by which it is enabled to produce the effect : For these 
are supposed to be synonimous. We must, therefore, 
know both the cause and effect, and the relation be- 
tween them. But do we pretend to be acquainted with 
the nature of the human soul and the nature of an idea, 
or the aptitude of the one to produce the other? This 
is a real creation ; a production of something out of 
nothing : Which implies a power so great, that it may 



1 It may be pretended, that the resistance which we meet with in bodies, 
obliging us frequently to exert our force, and call up all our power, this gives 
us the idea of force and power. It is this nisus, or strong endeavour, of which 
we are conscious, that is the original impression from which this idea is cop- 
ied. But, first, we attribute power to a vast number of objects, where we never 
can suppose this resistance or exertion of force to take place ; to the Supreme 
Being, who never meets with any resistance ; to the mind in its command 
over its ideas and limbs, in common thinking and motion, where the eilect 
follows immediately upon the will, without any exertion or summoning up of 
force ; to inanimate matter, which is not capable of this sentiment. Secondly, 
This sentiment of an endeavour to overcome resistance has no known con- 
nexion with any event: What follows it, we know by experience; but could 
not know it a priori. It must, however, be confessed, that the animal nisus } 
which we experience, though it can afford no accurate precise idea of power, 
enters very much into that vulgar, inaccurate idea, which is formed of it 



76 AN ENQUIR Y CONCERNING 

seem, at first sight, beyond the reach of any being, 
less than infinite. At least it must be owned, that 
such a power is not felt, nor known, nor even conceiv- 
able by the mind. We only feel the event, namely, 
the existence of an idea, consequent to a command of 
the will : But the manner, in which this operation is 
performed, the power by which it is produced, is en- 
tirely beyond our comprehension. 

Secondly, The command of the mind over itself is 
limited, as well as its command over the body; and 
these limits are not known by reason, or any acquain- 
tance with the nature of cause and effect, but only by 
experience and observation, as in all other natural 
events and in the operation of external objects. Our 
authority over our sentiments and passions is much 
weaker than that over our ideas ; and even the latter 
authority is circumscribed within very narrow bound- 
aries. Will any one pretend to assign the ultimate 
reason of these boundaries, or show why the power is 
deficient in one case, not in another. 

Thirdly, This self-command is very different at dif- 
ferent times. A man in health possesses more of it 
than one languishing with sickness. We are more 
master of our thoughts in the morning than in the ev- 
ening : Fasting, than after a full meal. Can we give 
any reason for these variations, except experience ? 
Where then is the power, of which we pretend to be 
conscious ? Is there not here, either in a spiritual or 
material substance, or both, some secret mechanism 
or structure of parts, upon which the effect depends, 
and which, being entirely unknown to us, renders the 
power or energy of the will equally unknown and 
incomprehensible? 

Volition is surely an act of the mind, with which 



HUMAN UNDERSTANDING. ?1 

we are sufficiently acquainted. Reflect upon it. Con- 
sider it on all sides. Do you find anything in it like 
this creative power, by which it raises from nothing a 
new idea, and with a kind of Fiat, imitates the omni- 
potence of its Maker, if I may be allowed so to speak, 
who called forth into existence all the various scenes 
of nature ? So far from being conscious of this energy 
in the will, it requires as certain experience as that of 
which we are possessed, to convince us that such ex- 
traordinary effects do ever result from a simple act of 
volition. 

The generality of mankind never find any difficulty 
in accounting for the more common and familiar oper- 
ations of nature — such as the descent of heavy bodies, 
the growth of plants, the generation of animals, or the 
nourishment of bodies by food : But suppose that, in 
all these cases, they perceive the very force or energy 
of the cause, by which it is connected with its effect, 
and is for ever infallible in its operation. They ac- 
quire, by long habit, such a turn of mind, that, upon 
the appearace of the cause, they immediately expect 
with assurance its usual attendant, and hardly con- 
ceive it possible that any other event could result from 
it. It is only on the discovery of extraordinary phae- 
nomena, such as earthquakes, pestilence, and prodi- 
gies of any kind, that they find themselves at a loss 
to assign a proper cause, and to explain the manner 
in which the effect is produced by it. It is usual for 
men, in such difficulties, to have recourse to some in- 
visible intelligent principle 1 as the immediate cause of 
that event which surprises them, and which, they think, 
cannot be accounted for from the common powers of 
nature. But philosophers, who carry their scrutiny a 

1 ©eos anb /oiij^avjjs. 



72 AN ENQ U1R Y CONCERNING 

little farther, immediately perceive that, even in the 
most familiar events, the energy of the cause is as un- 
intelligible as in the most unusual, and that we only 
learn by experience the frequent Conjunction of objects, 
without being ever able to comprehend anything like 
Connexion between them. Here, then, many philoso- 
phers think themselves obliged by reason to have re- 
course, on all occasions, to the same principle, which 
the vulgar never appeal to but in cases that appear 
miraculous and supernatural. They acknowledge mind 
and intelligence to be, not only the ultimate and orig- 
inal cause of all things, but the immediate and sole 
cause of every event which appears in nature. They 
pretend that those objects which are commonly denom- 
inated causes, are in reality nothing but occasions ; and 
that the true and direct principle of every effect is not 
any power or force in nature, but a volition of the 
Supreme Being, who wills that such particular objects 
should for ever be conjoined with each other. Instead 
of saying that one billard-ball moves another by a force 
which it has derived from the author of nature, it is 
the Deity himself, they say, who, by a particular voli- 
tion, moves the second ball, being determined to this 
operation by the impulse of the first ball, in conse- 
quence of those general laws which he has laid down 
to himself in the government of the universe. But 
philosophers advancing still in their inquiries, discover 
that, as we are totally ignorant of the power on which 
depends the mutual operation of bodies, we are no less 
ignorant of that power on which depends the operation 
of mind on body, or of body on mind ; nor are we 
able, either from our senses or consciousness, to assign 
the ultimate principle in one case more than in the 
other. The same ignorance, therefore, reduces them 



HUMAN UNDERSTANDING 73 

to the same conclusion. They assert that the Deity- 
is the immediate cause of the union between soul and 
body ; and that they are not the organs of sense, which, 
being agitated by external objects, produce sensations 
in the mind; but that it is a particular volition of our 
omnipotent Maker, which excites such a sensation, in 
consequence of such a motion in the organ. In like 
manner, it is not any energy in the will that produces 
local motion in our members : It is God himself, who 
is pleased to second our will, in itself impotent, and to 
command that motion which we erroneously attribute 
to our own power and efficacy. Nor do philosophers 
stop at this conclusion. They sometimes extend the 
same inference to the mind itself, in its internal opera- 
tions. Our mental vision or conception of ideas is 
nothing but a revelation made to us by our Maker. 
When we voluntarily turn our thoughts to any object, 
and raise up its image in the fancy, it is not the will 
which creates that idea : It is the universal Creator, 
who discovers it to the mind, and renders it present 
to us. 

Thus, according to these philosophers, every thing 
is full of God. Not content with the principle, that 
nothing exists but by his will, that nothing possesses 
any power but by his concession : They rob nature, 
and all created beings, of every power, in order to ren- 
der their dependence on the Deity still more sensible 
and immediate. They consider not that, by this the- 
ory, they diminish, instead of magnifying, the gran- 
deur of those attributes, which they affect so much to 
celebrate. It argues surely more power in the Deity 
to delegate a certain degree of power to inferior crea- 
tures, than to produce every thing by his own immedi- 
ate volition. It argues more wisdom to contrive at 



74 AN ENQUIRY CONCERNING 

first the fabric of the world with such perfect foresight 
that, of itself, and by its proper operation, it may serve 
all the purposes of providence, than if the great Crea- 
tor v/ere obliged every moment to adjust its parts, and 
animate by his breath all the wheels of that stupen- 
dous machine. 

But if we would have a more philosophical confu- 
tation of this theory, perhaps the two following reflec- 
tions may suffice. 

First, it seems to me that this theory of the univer- 
sal energy and operation of the Supreme Being is too 
bold ever to carry conviction with it to a man, suffici- 
ently apprized of the weakness of human reason, and 
the narrow limits to which it is confined in all its oper- 
ations. Though the chain of arguments which con- 
duct to it were ever so logical, there must arise a strong 
suspicion, if not an absolute assurance, that it has 
carried us quite beyond the reach of our faculties, 
when it leads to conclusions so extraordinary, and so 
remote from common life and experience. We are got 
into fairy land, long ere we have reached the last steps 
of our theory ; and there we have no reason to trust 
our common methods of argument, or to think that 
our usual analogies and probabilities have any author- 
ity. Our line is too short to fathom such immense 
abysses. And however we may flatter ourselves that 
we are guided, in every step which we take, by a kind 
of verisimilitude and experience, we may be assured 
that this fancied experience has no authority when we 
thus apply it to subjects that lie entirely out of the 
sphere of experience. But on this we shall have oc- 
casion to touch afterwards. 1 

Secondly, I cannot perceive any force in the argu- 

1 Section XII. 



HUMAN UNDERSTANDING 75 

ments on which this theory is founded. We are ig- 
norant, it is true, of the manner in which bodies oper- 
ate on each other : Their force or energy is entirely 
incomprehensible: But are we not equally ignorant 
of the manner or force by which a mind, even the su- 
preme mind, operates either on itself or on body? 
Whence, I beseech you, do we acquire any idea of it ? 
We have no sentiment or consciousness of this power 
in ourselves. We have no idea of the Supreme Being 
but what we learn from reflection on our own faculties. 
Were our ignorance, therefore, a good reason for re- 
jecting any thing, we should be led into that principle 
of denying all energy in the Supreme Being as much 
as in the grossest matter. We surely comprehend as 
little the operations of one as of the other. Is it more 
difficult to conceive that motion may arise from im- 
pulse than that it may arise from volition ? All we 
know is our profound ignorance in both cases. 1 

Part II. 

But to hasten to a conclusion of this argument, 
which is already drawn out to too great a length : We 
have sought in vain for an idea of power or necessary 
connexion in all the sources from which we could sup- 

1 1 need not examine at length the vis inertiae which is so much talked of 
in the new philosophy, and which is ascribed to matter. We find by experi- 
ence, that a body at rest or in motion continues for ever in its present state, 
till put from it by some new cause ; and that a body impelled takes as much 
motion from the impelling body as it acquires itself. Ihese are facts. When 
we call this a vis inertiae, we only mark these facts, without pretending to 
have any idea of the inert power; in the same manner as, when we talk of 
gravity, we mean certain effects, without comprehending that active power. 
It was never the meaning of Sir Isaac Newton to rob second causes of all 
force or energy ; though some of his followers have endeavoured to establish 
that theory upon his authority. On the contrary, that great philosopher had 
recourse to an etherial active fluid to explain his universal attraction ; though 
he was so cautious and modest as to allow, that it was a mere hypothesis, not 



76 AN ENQ UIR Y CONCERNING 

pose it to be derived. It appears that, in single in- 
stances of the operation of bodies, we never can, by 
our utmost scrutiny, discover any thing but one event 
following another, without being able to comprehend 
any force or power by which the cause operates, or 
any connexion between it and its supposed effect. The 
same difficulty occurs in contemplating the operations 
of mind on body — -where we observe the motion of the 
latter to follow upon the volition of the former, but 
are not able to observe or conceive the tie which binds 
together the motion and volition, or the energy by 
which the mind produces this effect. The authority 
of the will over its own faculties and ideas is not a whit 
more comprehensible : So that, upon the whole, there 
appears not, throughout all nature, any one instance 
of connexion which is conceivable by us. All events 
seem entirely loose and separate. One event follows 
another ; but we never can observe any tie between 
them. They seem conjoined, but never connected. And 
as we can have no idea of any thing which never ap- 
peared to our outward sense or inward sentiment, the 
necessary conclusion seems to be that we have no idea 
of connexion or power at all, and that these words are 
absolutely without any meaning, when employed 
either in philosophical reasonings or common life. 

But there still remains one method of avoiding this 
conclusion, and one source which we have not yet 
examined. When any natural object or event is pre- 

to be insisted on, without more experiments. I must confess, that there is 
something in the fate of opinions a little extraordinary. Des Cartes insinu- 
ated that doctrine of the universal and sole efficacy of the Deity, without in- 
sisting on it. Malebranche and other Cartesians made it the foundation of 
all their philosophy. It had, however, no authority in England. Locke, 
Clarke, and Cudworth, never so much as take notice of it, but suppose all 
along, that matter has a real, though subordinate and derived power. By 
what means has it become so prevalent among our modern metaphysicians? 



HUMAN UNDERSTANDING 77 

sented, it is impossible for us, by any sagacity or pen- 
etration, to discover, or even conjecture, without ex- 
perience, what event will result from it, or to carry 
our foresight beyond that object which is immediately 
present to the memory and senses. Even after one 
instance or experiment where we have observed a par- 
ticular event to follow upon another, we are not 
entitled to form a general rule, or foretell what will 
happen in like cases ; it being justly esteemed an un- 
pardonable temerity to judge of the whole course of na- 
ture from one single experiment, however accurate or 
certain. But when one particular species of event has 
always, in all instances, been conjoined with another, 
we make no longer any scruple of foretelling one upon 
the appearance of the other, and of employing that 
reasoning which can alone assure us of any matter of 
fact or existence. We then call the one object, Cause ; 
the other, Effect. We suppose that there is some 
connexion between them \ some power in the one, by 
which it infallibly produces the other, and operates 
with the greatest certainty and strongest necessity. 

It appears, then, that this idea of a necessary con. 
nexion among events arises from a number of similar 
instances which occur of the constant conjunction of 
these events ; nor can that idea ever be suggested by 
any one of these instances, surveyed in all possible 
lights and positions. But there is nothing in a num. 
ber of instances, different from every single instance, 
which is supposed to be exactly similar ; except only, 
that after a repetition of similar instances, the mind 
is carried by habit, upon the appearance of one event, 
to expect its usual attendant, and to believe that it will 
exist. This connexion, therefore, which we feel, in the 
mind, this customary transition of the imagination 



78 AN ENQUIRY CONCERNING 

from one object to its usual attendant, is the sentiment 
or impression from which we form the idea of power 
or necessary connexion. Nothing farther is in the 
case. Contemplate the subject on all sides ; you will 
never find any other origin of that idea. This is the 
sole difference between one instance, from which we 
can never receive the idea of connexion, and a number 
of similar instances, by which it is suggested. The first 
time a man saw the communication of motion by im- 
pulse, as by the shock of two billiard balls, he could 
not pronounce that the one event was connected: but 
only that it was conjoined with the other. After he has 
observed several instances of this nature, he then pro- 
nounces them to be connected. What alteration has 
happened to give rise to this new idea of connexion ? 
Nothing but that he now feels these events to be con- 
nected in his imagination, and can readily foretell the 
existence of one from the appearance of the other. 
When we say, therefore, that one object is connected 
with another, we mean only that they have acquired 
a connexion in our thought, and give rise to this infer- 
ence, by which they become proofs of each other's ex- 
istence : A conclusion which is somewhat extraordi- 
nary, but which seems founded on sufficient evidence. 
Nor will its evidence be weakened by any general dif- 
fidence of the understanding, or sceptical suspicion 
concerning every conclusion which is new and extra- 
ordinary. No conclusions can be more agreeable to 
scepticism than such as make discoveries concerning 
the weakness and narrow limits of human reason and 
capacity. 

And what stronger instance can be produced of the 
surprising ignorance and weakness of the understand- 
ing than the present ? For surely, if there be any re- 



HUMAN UNDERSTANDING. 79 

lation among objects which it imports to us to know 
perfectly, it is that of cause and effect. On this are 
founded all our reasonings concerning matter of fact 
or existence. By means of it alone we attain any as- 
surance concerning objects which are removed from 
the present testimony of our memory and senses. The 
only immediate utility of all sciences, is to teach us, 
how to control and regulate future events by their 
causes. Our thoughts and enquiries are, therefore, 
every moment, employed about this relation : Yet so 
imperfect are the ideas which we form concerning it, 
that it is impossible to give any just definition of cause, 
except what is drawn from something extraneous and 
foreign to it. Similar objects are always conjoined with 
similar. Of this we have experience. Suitably to this 
experience, therefore, we may define a cause to be an 
object, followed by another, and where all the objects simi- 
lar to the first are followed by objects similar to the second. 
Or in other words where, if the first object had not been, 
rhe second never had existed. The appearance of a cause 
always conveys the mind, by a customary transition, 
to the idea of the effect. Of this also we have experi- 
ence. We may, therefore, suitably to this experience, 
form another definition of cause, and call it, an object 
followed by another, and whose appearance always conveys 
the thought to that other. But though both these defi- 
nitions be drawn from circumstances foreign to the 
cause, we cannot remedy this inconvenience, or attain 
any more perfect definition, which may point out that 
circumstance in the cause, which gives it a connexion 
with its effect. We have no idea of this connexion, 
nor even any distinct notion what it is we desire to 
know, when we endeavour at a conception of it. We 
say, for instance, that the vibration of this string is 






8o AN ENQ UIR Y CONCERNING 

the cause of this particular sound. But what do we 
mean by that affirmation ? We either mean that this 
vibration is followed by this sound, and that all similar 
vibrations have been followed by similar sounds : Or, that 
this vibration is followed by this sound, and that upoti thd 
appearance of one the i?iind anticipates the senses, and forms 
immediately an idea of the other. We may consider the 
relation of cause and effect in either of these two 
lights; but beyond these, we have no idea of it. 1 

To recapitulate, therefore, the reasonings of this 
section : Every idea is copied from some preceding 
impression or sentiment; and where we cannot find 
any impression, we may be certain that there is no 
idea. In all single instances of the operation of bodies 
! or minds, there is nothing that produces any impres- 

1 According to these explications and definitions, the idea of power is re- 
lative as much as that of cause ; and both have a reference to an effect, or 
some other event constantly conjoined with the former. When we consider 
the unknown circumstance of an object, by which the degree or quantity of 
its effect is fixed and determined, we call that its power: And accordingly, 
it is allowed by all philosophers, that the effect is the measure of the power. 
But if they had any idea of power, as it is in itself, why could not they meas- 
ure it in itself ? The dispute whether the force of a body in motion be as its 
velocity, or the square of its velocity; this dispute, I say, needed not be de- 
cided by comparing its effects in equal or unequal times ; but by a direct 
mensuration and comparison. 

As to the frequent use of the words, Force, Power, Energy, &c, which ev- 
ery where occur in common conversation, as well as in philosophy ; that is 
no proof, that we are acquainted, in any instance, with the connecting princi* 
pie between cause and effect, or can account ultimately for the production of 
one thing to another. These words, as commonly used, have very loose 
meanings annexed to them; and their ideas are very uncertain and confused. 
No animal can put external bodies in motion without the sentiment of a nisus 
or endeavour; and every animal has a sentiment or feeling from the stroke 
or blow of an external object, that is in motion. These sensations, which are 
merely animal, and from which we can a priori draw no inference, we are 
apt to transfer to inanimate objects, and to suppose, that they have some such 
feelings, whenever they transfer or receive motion. With regard to energies, 
which are exerted, without our annexing to them any idea of communicated 
motion, we consider only the constant experienced conjunction of the events; 
and as we feel a customary connexion between the ideas, we transfer that 
feeling to the objects; as nothing is more usual than to apply to external bodies 
every internal sensation, which they occasion. 



HUMAN UNDERSTANDING. 81 

sion, nor consequently can suggest any idea of power 
or necessary connexion. But when many uniform in- 
stances appear, and the same object is always followed 
by the same event ; we then begin to entertain the 
notion of cause and connexion. We then feel a new 
sentiment or impressson, to wit, a customary connex- 
ion in the thought or imagination between one object 
and its usual attendant ; and this sentiment is the 
original of that idea which we seek for. For as this 
idea arises from a number of similar instances, and 
not from any single instance, it must arise from that cir- 
cumstance, in which the number of instances differ 
from every individual instance. But this customary 
connexion or transition of the imagination is the only 
circumstance in which they differ. In every other par- 
ticular they are alike. The first instance which we saw 
of motion communicated by the shock of two billiard 
balls (to return to this obvious illustration) is exactly 
similar to any instance that may, at present, occur to 
us ; except only, that we could not, at first, infer one 
event from the other ; which we are enabled to do at 
present, after so long a course of uniform experience. 
I know not whether the reader will readily apprehend 
this reasoning. I am afraid that, should I multiply 
words about it, or throw it into a greater variety of 
lights, it would only become more obscure and intri- 
cate. In all abstract reasonings there is one point of 
view which, if we can happily hit, we shall go farther 
towards illustrating the subject than by all the elo- 
quence in the world. This point of view we should 
endeavour to reach, and reserve the flowers of rhetoric 
for subjects which are more adapted to them. 



SECTION VIII. 

OF LIBERTY AND NECESSITY. 

Part I. 

{T might reasonably be expected in questions which 
have been canvassed and disputed with great eager- 
ness, since the first origin of science and philosophy, 
that the meaning of all the terms, at least, should 
have been agreed upon among the disputants; and 
our enquiries, in the course of two thousand years, 
been able to pass from words to the true and real sub- 
ject of the controversy. For how easy may it seem 
to give exact definitions of the terms employed in rea- 
soning, and make these definitions, not the mere sound 
of words, the object of future scrutiny and examina- 
tion? But if we consider the matter more narrowly, 
we shall be apt to draw a quite opposite conclusion. 
From this circumstance alone, that a controversy has 
been long kept on foot, and remains still undecided, 
we may presume that there is some ambiguity in the 
expression, and that the disputants affix different ideas 
to the terms employed in the controversy. For as the 
faculties of the mind are supposed to be naturally alike 
in every individual ; otherwise nothing could be more 
fruitless than to reason or dispute together; it were 
impossible, if men affix the same ideas to their terms, 
that they could so long form different opinions of the 
same subject ; especially when they communicate their 



HUMAN UNDERSTANDING. 83 

views, and each party turn themselves on all sides, in 
search of arguments which may give them the victory 
over their antagonists. It is true, if men attempt the 
discussion of questions which lie entirely beyond the 
reach of human capacity, such as those concerning 
the origin of worlds, or the economy of the intellectual 
system or region of spirits, they may long beat the air 
in their fruitless contests, and never arrive at any de- 
terminate conclusion. But if the question regard any 
subject of common life and experience, nothing, one 
would think, could preserve the dispute so long unde- 
cided but some ambiguous expressions, which keep 
the antagonists still at a distance, and hinder them 
from grappling with each other. 

This has been the case in the long disputed ques- 
tion concerning liberty and necessity; and to so re- 
markable a degree that, if I be not much mistaken, 
we shall find, that all mankind, both learned and ig- 
norant, have always been of the same opinion with 
regard to this subject, and that a few intelligible defi- 
nitions would immediately have put an end to the 
whole controversy. I own that this dispute has been 
so much canvassed on all hands, and has led philoso- 
phers into such a labyrinth of obscure sophistry, that 
it is no wonder, if a sensible reader indulge his ease 
so far as to turn a deaf ear to the proposal of such a 
question, from which he can expect neither instruction 
nor entertainment. But the state of the argument here 
proposed may, perhaps, serve to renew his attention ; 
as it has more novelty, promises at least some decision 
of the controversy, and will not much disturb his ease 
by any intricate or obscure reasoning. 

I hope, therefore, to make it appear that all men 
have ever agreed in the doctrine both of necessity and 



8 4 AN ENQ UIR Y CONCERNING 

of liberty, according to any reasonable sense, which 
can be put on these terms ; and that the whole con- 
troversy has hitherto turned merely upon words. We 
shall begin with examining the doctrine of necessity. 

It is universally allowed that matter, in all its op- 
erations, is actuated by a necessary force, and that 
every natural effect is so precisely determined by the 
energy of its cause that no other effect, in such par- 
ticular circumstances, could possibly have resulted 
from it. The degree and direction of every motion is, 
by the laws of nature, prescribed with such exactness 
chat a living creature may as soon arise from the shock 
of two bodies as motion in any other degree or direc- 
tion than what is actually produced by it. Would we, 
therefore, form a just and precise idea of necessity, we 
must consider whence that idea arises when we apply 
it to the operation of bodies. 

It seems evident that, if all the scenes of nature 
were continually shifted in such a manner that no two 
events bore any resemblance to each other, but every 
object was entirely new, without any similitude to 
whatever had been seen before, w r e should never, in 
that case, have attained the least idea of necessity, or 
of a connexion among these objects. We might say, 
upon such a supposition, that one object or event has 
followed another; not that one was produced by the 
other. The relation of cause and effect must be utterly 
unknown to mankind. Inference and reasoning con- 
cerning the operations of nature would, from that mo- 
ment, be at an end ; and the memory and senses re- 
main the only canals, by which the knowledge of any 
real existence could possibly have access to the mind. 
Our idea, therefore, of necessity and causation arises 
entirely from the uniformity observable in the opera- 



HUMAN UNDERSTANDING. 85 

tions of nature, where similar objects are constantly 
conjoined together, and the mind is determined by 
custom to infer the one from the appearance of the 
other. These two circumstances form the whole of 
that necessity, which we ascribe to matter. Beyond 
the constant conjunction of similar objects, and the con- 
sequent inference from one to the other, we have no 
notion of any necessity or connexion. 

If it appear, therefore, that all mankind have ever 
allowed, without any doubt or hesitation, that these 
two circumstances take place in the voluntary actions 
of men, and in the operations of mind ; it must follow, 
'that all mankind have ever agreed in the doctrine of 
necessity, and that they have hitherto disputed, merely 
for not understanding each other. 

As to the first circumstance, the constant and reg- 
ular conjunction of similar events, we may possibly 
satisfy ourselves by the following considerations. It 
is universally acknowledged that there is a great uni- 
formity among the actions of men, in all nations and 
ages, and that human nature remains still the same, 
in its principles and operations. The same motives 
always produce the same actions : The same events 
follow from the same causes. Ambition, avarice, self- 
love, vanity, friendship, generosity, public spirit : 
these passions, mixed in various degrees, and distrib- 
uted through society, have been, from the beginning 
of the world, and still are, the source of all the actions 
and enterprises, which have ever been observed among 
mankind. Would you know the sentiments, inclina- 
tions, and course of life of the Greeks and Romans ? 
Study well the temper and actions of the French and 
English : You cannot be much mistaken in transfer- 
ring to the former most of the observations which you 



86 AN ENQ UIR Y CONCERNING 

have made with regard to the latter. Mankind are so 
much the same, in all times and places, that history 
informs us of nothing new or strange in this particular. 
Its chief use is only to discover the constant and uni- 
versal principles of human nature, by showing men in 
all varieties of circumstances and situations, and fur- 
nishing us with materials from which we may form our 
observations and become acquainted with the regular 
springs of human action and behaviour. These rec- 
ords of wars, intrigues, factions, and revolutions, are 
so many collections of experiments, by which the poli- 
tician or moral philosopher fixes the principles of his 
science, in the same manner as the physician or natu- 
ral philosopher becomes acquainted with the nature 
of plants, minerals, and other external objects, by the 
experiments which he forms concerning them. Nor 
are the earth, water, and other elements, examined 
by Aristotle, and Hippocrates, more like to those 
which at present lie under our observation than the 
men described by Polybius and Tacitus are to those 
who now govern the world. 

Should a traveller, returning from a far country, 
bring us an account of men, wholly different from any 
with whom we were ever acquainted; men, who were 
entirely divested of avarice, ambition, or revenge ; 
who knew no pleasure but friendship, generosity, and 
public spirit ; we should immediately, from these cir- 
cumstances, detect the falsehood, and prove him a 
liar, with the same certainty as if he had stuffed his 
narration with stories of centaurs and dragons, mira- 
cles and prodigies. And if we would explode any for- 
gery in history, we cannot make use of a more convin- 
cing argument, than to prove, that the actions ascribed 
to any person are directly contrary to the course of 



HUMAN UNDERSTANDING. 8? 

nature, and that no human motives, in such circum- 
stances, could ever induce him to such a conduct. 
The veracity of Quintus Curtius is as much to be sus- 
pected, when he describes the supernatural courage 
of Alexander, by which he was hurried on singly to 
attack multitudes, as when he describes his supernat- 
ural force and activity, by which he was able to resist 
them. So readily and universally do we acknowledge 
a uniformity in human motives and actions as well as 
in the operations of body. 

Hence likewise the benefit of that experience, ac- 
quired by long life and a variety of business and com- 
pany, in order to instruct us in the principles of hu- 
man nature, and regulate our future conduct, as well 
as speculation. By means of this guide, we mount up 
to the knowledge of men's inclinations and motives, 
from their actions, expressions, and even gestures; 
and again descend to the interpretation of their actions 
from our knowledge of their motives and inclinations. 
The general observations treasured up by a course of 
experience, give us the clue of human nature, and 
teach us to unravel all its intricacies. Pretexts and 
appearances no longer deceive us. Public declarations 
pass for the specious colouring of a cause. And though 
virtue and honour be allowed their proper weight and 
authority, that perfect disinterestedness, so often pre- 
tended to, is never expected in multitudes and parties; 
seldom in their leaders ; and scarcely even in individ- 
uals of any rank or station. But were there no uni- 
formity in human actions, and were every experiment 
which we could form of this kind irregular and anom- 
alous, it were impossible to collect any general obser- 
vations concerning mankind ; and no experience, how- 
ever accurately digested by reflection, would ever 



88 AN ENQUIRY CONCERNING 

serve to any purpose. Why is the aged husbandman 
more skilful in his calling than the young beginner 
but because there is a certain uniformity in the opera- 
tion of the sun, rain, and earth towards the production 
of vegetables ; and experience teaches the old practi- 
tioner the rules by which this operation is governed 
and directed. 

We must not, however, expect that this uniformity 
of human actions should be carried to such a length 
as that all men, in the same circumstances, will always 
act precisely in the same manner, without making any 
allowance for the diversity of characters, prejudices, 
and opinions. Such a uniformity in every particular, 
is found in no part of nature. On the contrary, from 
observing the variety of conduct in different men, we 
are enabled to form a greater variety of maxims, which 
still suppose a degree of uniformity and regularity. 

Are the manners of men different in different ages 
and countries ? We learn thence the great force of 
custom and education, which mould the human mind 
from its infancy and form it into a fixed and established 
character. Is the behaviour and conduct of the one 
sex very unlike that of the other ? Is it thence we be- 
come acquainted with the different characters which 
nature has impressed upon the sexes, and which she 
preserves with constancy and regularity? Are the ac- 
tions of the same person much diversified in the dif- 
ferent periods of his life, from infancy to old age ? 
This affords room for many general observations con- 
cerning the gradual change of our sentiments and in- 
clinations, and the different maxims which prevail in 
the different ages of human creatures. Even the char- 
acters, which are peculiar to each individual, have a 
uniformity in their influence ; otherwise our acquain- 



HUMAN UNDERSTANDING. 8g 

tance with the persons and our observation of their 
conduct could never teach us their dispositions, or 
serve to direct our behaviour with regard to them. 

I grant it possible to find some actions, which seem 
to have no regular connexion with any known motives, 
and are exceptions to all the measures of conduct 
which have ever been established for the government 
of men. But if we would willingly know what judge- 
ment should be formed of such irregular and extraor- 
dinary actions, we may consider the sentiments com- 
monly entertained with regard to those irregular 
events which appear in the course of nature, and the 
operations of external objects. All causes are not con- 
joined to their usual effects with like uniformity. An 
artificer, who handles only dead matter, may be dis- 
appointed of his aim, as well as the politician, who 
directs the conduct of sensible and intelligent agents. 

The vulgar, who take things according to their first 
appearance, attribute the uncertainty of events to such 
an uncertainty in the causes as makes the latter often 
fail of their usual influence ; though they meet with 
no impediment in their operation. But philosophers, 
observing that, almost in every part of nature, there 
is contained a vast variety of springs and principles, 
which are hid, by reason of their minuteness or re- 
moteness, find, that it is at least possible the contra- 
riety of events may not proceed from any contingency 
in the cause, but from the secret operation of contrary 
causes. This possibility is converted into certainty 
by farther observation, when they remark that, upon 
an exact scrutiny, a contrariety of effects always be- 
trays a contrariety of causes, and proceeds from their 
mutual opposition. A peasant can give no better rea- 
son for the stopping of any clock or watch than to 



go AN ENQ UIR Y CONCERNING 

say that it does not commonly go right : But an artist 
easily perceives that the same force in the spring or 
pendulum has always the same influence on the wheels; 
but fails of its usual effect, perhaps by reason of a 
grain of dust, which puts a stop to the whole move- 
ment. From the observation of several parallel in- 
stances, philosophers form a maxim that the connexion 
between all causes and effects is equally necessary, 
and that its seeming uncertainty in some instance s 
proceeds from the secret opposition of contrary causcp. 

Thus, for instance, in the human body, when the 
usual symptoms of health or sickness disappoint our 
expectation ; when medicines operate not with their 
wonted powers; when irregular events follow from any 
particular cause; the philosopher and physician are 
not surprised at the matter, nor are ever tempted to 
deny, in general, the necessity and uniformity of those 
principles by which the animal economy is conducted. 
They know that a human body is a mighty compli- 
cated machine : That many secret powers lurk in it, 
which are altogether beyond our comprehension : That 
to us it must often appear very uncertain in its opera- 
tions : And that therefore the irregular events, which 
outwardly discover themselves, can be no proof that 
the laws of nature are not observed with the greatest 
regularity in its internal operations and government. 

The philosopher, if he be consistent, must apply 
the same reasoning to the actions and volitions of in- 
telligent agents. The most irregular and unexpected 
resolutions of men may frequently be accounted for by 
those who know every particular circumstance of their 
character and situation. A peison of an obliging dis- 
position gives a peevish answer : But he has the tooth- 
ache, or has not dined. A stupid fellow discovers an 



HUMAN UNDERSTANDING. 91 

uncommon alacrity in his carriage : But he has met 
with a sudden piece of good fortune. Or even when 
an action, as sometimes happens, cannot be particu- 
larly accounted for, either by the person himself or by 
others ; we know, in general, that the characters of 
men are, to a certain degree, inconstant and irregular. 
This is, in a manner, the constant character of human 
nature; though it be applicable, in a more particular 
manner, to some persons who have no fixed rule for 
their conduct, but proceed in a continued course of 
caprice and inconstancy. The internal principles and 
motives may operate in a uniform manner, notwith- 
standing these seeming irregularities ; in the same 
manner as the winds, rain, clouds, and other varia- 
tions of the weather are supposed to be governed by 
steady principles ; though not easily discoverable by 
human sagacity and enquiry. 

Thus it appears, not only that the conjunction be- 
tween motives and voluntary actions is as regular and 
uniform as that between the cause and effect in any 
part of nature ; but also that this regular conjunction 
has been universally acknowledged among mankind, 
and has never been the subject of dispute, either in 
philosophy or common life. Now, as it is from past 
experience that we draw all inferences concerning the 
future, and as we conclude that objects will always be 
conjoined together which we find to have always been 
conjoined ; it may seem superfluous to prove that this 
experienced uniformity in human actions is a source 
whence we draw inferences concerning them. But in 
order to throw the argument into a greater variety of 
lights we shall also insist, though briefly, on this 
latter topic. 

The mutual dependence of men is so great in all 



92 AN ENQ UIR Y CONCERNING 

societies that scarce any human action is entirely com- 
plete in itself, or is performed without some reference 
to the actions of others, which are requisite to make 
it answer fully the intention of the agent. The poor- 
est artificer, who labours alone, expects at least the 
protection of the magistrate, to ensure him the enjoy- 
ment of the fruits of his labour. He also expects that, 
when he carries his goods to market, and offers them 
at a reasonable price, he shall find purchasers, and 
shall be able, by the money he acquires, to engage 
others to supply him with those commodities which 
are requisite for his subsistence. In proportion as men 
extend their dealings, and render their intercourse 
with others more complicated, they always compre- 
hend, in their schemes of life, a greater variety of vol- 
untary actions, which they expect, from the proper 
motives, to co-operate with their own. In all these 
conclusions they take their measures from past expe- 
rience, in the same manner as in their reasonings con- 
cerning external objects ; and firmly believe that men, 
as well as all the elements, are to continue, in their 
operations, the same that they have ever found them. 
A manufacturer reckons upon the labour of his ser- 
vants for the execution of any work as much as upon 
the tools which he employs, and would be equally 
surprised were his expectations disappointed. In 
short, this experimental inference and reasoning con- 
cerning the actions of others enters so much into 
human life, that no man, while awake, is ever a mo- 
ment without employing it. Have we not reason, 
therefore, to affirm that all mankind have always 
agreed in the doctrine of necessity according to the 
foregoing definition and explication of it ? 

Nor have philosophers ever entertained a different 



HUMAN UNDERSTANDING. 93 

opinion from the people in this particular. For, not 
to mention that almost every action of their life sup- 
poses that opinion, there are even few of the specula- 
tive parts of learning to which it is not essential. What 
would become of history, had we not a dependence on 
the veracity of the historian according to the experi- 
ence which we have had of mankind ? How could 
politics be a science, if laws and forms of government 
had not a uniform influence upon society ? Where 
would be the foundation of morals, if particular char- 
acters had no certain or determinate power to produce 
particular sentiments, and if these sentiments had no 
constant operation on actions ? And with what pre- 
tence could we employ our criticism upon any poet or 
polite author, if we could not pronounce the conduct 
and sentiments of his actors either natural or unnatu- 
ral to such characters, and in such circumstances? 
It seems almost impossible, therefore, to engage either 
in science or action of any kind without acknowledg- 
ing the doctrine of necessity, and this inference from 
motive to voluntary actions, from characters to con- 
duct. 

And indeed, when we consider how aptly ?iaturat 
and moral evidence link together, and form only one 
chain of argument, we shall make no scruple to allow 
that they are of the same nature, and derived from the 
same principles. A prisoner who has neither money 
nor interest, discovers the impossibility of his escape, 
as well when he considers the obstinacy of the goaler, 
as the walls and bars with which he is surrounded; 
and, in all attempts for his freedom, chooses rather to 
work upon the stone and iron of the one, than upon 
the inflexible nature of the other. The same prisoner, 
when conducted to the scaffold, foresees his death as 



94 AN ENQ UIR Y CONCERNING 

certainly from the constancy and fidelity of his guards, 
as from the operation of the axe or wheel. His mind 
runs along a certain train of ideas : The refusal of the 
soldiers to consent to his escape ; the action of the 
executioner ; the separation of the head and body ; 
bleeding, convulsive motions, and death. Here is a 
connected chain of natural causes and voluntary ac- 
tions ; but the mind feels no difference between them 
in passing from one link to another : Nor is less cer- 
tain of the future event than if it were connected with 
the objects present to the memory or senses, by a train 
of causes, cemented together by what we are pleased 
to call a physical necessity. The same experienced 
union has the same effect on the mind, whether the 
united objects be motives, volition, and actions ; or 
figure and motion. We may change the name of 
things ; but their nature and their operation on the 
understanding never change. 

Were a man, whom I know to be honest and opu- 
lent, and with whom I live in intimate friendship, to 
come into my house, where I am surrounded with my 
servants, I rest assured that he is not to stab me be- 
fore he leaves it in order to rob me of my silver stand- 
ish; and I no more suspect this event than the fall- 
ing of the house itself, which is new, and solidly built 
and founded. — But he may have been seized with a sud- 
den and unknown frenzy . — So may a sudden earthquake 
arise, and shake and tumble my house about my ears- 
I shall therefore change the suppositions. I shall say 
that I know with certainty that he is not to put his 
hand into the fire and hold it there till it be consumed : 
And this event, I think I can foretell with the same 
assurance, as that, if he throw himself out at the win- 
dow, and meet with no obstruction, he will not remain 



HUMAN UNDERSTANDING. 95 

a moment suspended in the air. No suspicion of an 
unknown frenz}' can give the least possibility to the 
former event, which is so contrary to all the known 
principles of human nature. A man who at noon 
leaves his purse full of gold on the pavement at Char- 
ing-Cross, may as well expect that it will fly away like 
a feather, as that he will find it untouched an hour 
after. Above one half of human reasonings contain 
inferences of a similar nature, attended with more or 
less degrees of certainty proportioned to our experi- 
ence of the usual conduct of mankind in such partic- 
ular situations. 

I have frequently considered, what could possibly 
be the reason why all mankind, though they have 
ever, without hesitation, acknowledged the doctrine 
of necessity in their whole practice and reasoning, 
have yet not discovered such a reluctance to acknowl- 
edge it in words, and have rather shown a propensity, 
in all ages, to profess the contrary opinion. The mat- 
ter, I think, may be accounted for after the following 
manner. If we examine the operations of body, and 
the production of effects from their causes, we shall 
find that all our faculties can never carry us farther in 
our knowledge of this relation than barely to observe 
that particular objects are constantly conjoined together, 
and that the mind is carried, by a customary transition, 
from the appearance of one to the belief of the other. 
But though this conclusion concerning human ignor- 
ance be the result of the strictest scrutiny of this sub- 
ject, men still entertain a strong propensity to believe 
that they penetrate farther into the pow r ers of nature, 
and perceive something like a necessary connexion 
between the cause and the effect. When again they 
turn their reflections towards the operations of their 



9 6 AN ENQ UIR Y CONCERNING 

own minds, and feel no such connexion of the motive 
and the action ; they are thence apt to suppose, that 
there is a difference between the effects which result 
from material force, and those which arise from 
thought and intelligence. But being once convinced 
that we know nothing farther of causation of any kind 
than merely the constant conjunction of objects, and the 
consequent inference of the mind from one to another, 
and finding that these two circumstances are univer- 
sally allowed to have place in voluntary actions ; we 
may be more easily led to own the same necessity 
common to all causes. And though this reasoning 
may contradict the systems of many philosophers, in 
ascribing necessity to the determinations of the will, 
we shall find, upon reflection, that they dissent from 
it in words only, not in their real sentiment. Neces- 
sity, according to the sense in which it is here taken, 
has never yet been rejected, nor can ever, I think, be 
rejected by any philosopher. It may only, perhaps, 
be pretended that the mind can perceive, in the opera- 
tions of matter, some farther connexion between the 
cause and effect ; and connexion that has not place in 
voluntary actions of intelligent beings. Now whether 
it be so or not, can only appear upon examination ; 
and it is incumbent on these philosophers to make 
good their assertion, by defining or describing that 
necessity, and pointing it out to us in the operations 
of material causes. 

It would seem, indeed, that men begin at the wrong 
end of this question concerning liberty and necessity, 
when they enter upon it by examining the faculties of 
the soul, the influence of the understanding, and the 
operations of the will. Let them first discuss a more 
simple question, namely, the operations of body and 



HUMAN UNDERSTANDING. 97 

of brute unintelligent matter ; and try whether they 
can there form any idea of causation and necessity, 
except that of a constant conjunction of objects, and 
subsequent inference of the mind from one to another. 
If these circumstances form, in reality, the whole of 
that necessity, which we conceive in matter, and if 
these circumstances be also universally acknowledged 
to take place in the operations of the mind, the dis- 
pute is at an end ; at least, must be owned to be 
thenceforth merely verbal. But as long as we will 
rashly suppose, that we have some farther idea of 
necessity and causation in the operations of external 
objects; at the same time, that we can find nothing 
farther in the voluntary actions of the mind ; there is 
no possibility of bringing the question to any deter- 
minate issue, while we proceed upon so erroneous a 
supposition. The only method of undeceiving us is 
to mount up higher ; to examine the narrow extent of 
science when applied to material causes ; and to con- 
vince ourselves that all we know of them is the con- 
stant conjunction and inference above mentioned. We 
may, perhaps, find that it is with difficulty we are in- 
duced to fix such narrow limits to human understand- 
ing : But we can afterwards find no difficulty when 
we come to apply this doctrine to the actions of the 
will. For as it is evident that these have a regular 
conjunction with motives and circumstances and char- 
acters, and as we always draw inferences from one to 
the other, we must be obliged to acknowledge in words 
that necessity, which we have already avowed, in 
every deliberation of our lives, and in every step of 
our conduct and behaviour. 1 

1 The prevalence of the doctrine of liberty may be accounted for, from 
another cause, viz. a false sensation or seeming experience which we have, 



9$ AN ENQUIR Y CONCERNING 

But to proceed in this reconciling project with re- 
gard to the question of liberty and necessity ; the most 
contentious question of metaphysics, the most con- 
tentious science ; it will not require many words to 
prove, that all mankind have ever agreed in the doc- 
trine of liberty as well as in that of necessity, and that 
the whole dispute, in this respect also, has been hith- 
erto merely verbal. For what is meant by liberty, 
when applied to voluntary actions ? We cannot surely 
mean that actions have so little connexion with mo- 
tives, inclinations, and circumstances, that one does 
not follow with a certain degree of uniformity from the 
other, and that one affords no inference by which we 
can conclude the existence of the other. For these are 

or may have, of liberty or indifference, in many of our actions. The necessity 
of any action, whether of matter or of mind, is not, properly speaking, a qual- 
ity in the agent, but in any thinking or intelligent being, who may consider 
the action; and it consists chiefly in the determination of his thoughts to 
infer the existence of that action from some preceding objects; as liberty, 
when opposed to necessity, is nothing but the want of that determination, 
and a certain looseness or indifference, which we feel, in passing, or not 
passing, from the idea of one object to that of any succeeding one. Now we 
may observe, that, though, in reflecting on human actions, we seldom feel 
such a looseness, or indifference, but are commonly able to infer them with 
considerable certainty from their motives, and from the dispositions of the 
agent; yet it frequently happens, that, \n performing the actions themselves, 
we are sensible of something like it: And as all resembling objects are readily 
taken for each other, this has been employed as a demonstrative and even 
intuitive proof of human liberty. We feel, that our actions are subject to our 
will, on most occasions; and imagine we feel, that the will itself is subject 
to nothing, because, when by a denial of it we are provoked to try, we feel, 
that it moves easily every way, and produces an image of itself (or a Velleity- 
as it is called in the schools) even on that side, on which it did not settle, 
This image, or faint motion, we persuade ourselves, could, at that time, have 
been compleated into the thing itself; because, should that be denied, we 
find, upon a second trial, that, at present, it can. We consider not, that the 
fantastical desire of shewing liberty, is here the motive of our actions. And 
it seems certain, that, however we may imagine we feel a liberty within our- 
selves, a spectator can commonly infer our actions from our motives and 
character; and even where he cannot, he concludes in general, that he might, 
were he perfectly acquainted with every circumstance of our situation and 
temper, and the most secret springs of our complexion and disposition. Now 
this is the very essence of necessity, according to the foregoing doctrine. 



HUMAKf UNDERSTANDING. 99 

plain and acknowledged matters of fact. By liberty, 
then, we can only mean a power of acting or not acting, 
according to the determinations of the will; that is, if we 
choose to remain at rest, we may ; if we choose to 
move, we also may. Now this hypothetical liberty is 
universally allowed to belong to every one who is not 
a prisoner and in chains. Here, then, is no subject 
of dispute. 

Whatever definition we may give of liberty, we 
should be careful to observe two requisite circum- 
stances ; first, that it be consistent with plain matter 
of fact ; secondly, that it be consistent with itself. If 
we observe these circumstances, and render our defi- 
nition intelligible, I am persuaded that all mankind 
will be found of one opinion with regard to it. 

It is universally allowed that nothing exists with- 
out a cause of its existence, and that chance, when 
strictly examined, is a mere negative word, and means 
not any real power which has anywhere a being in 
nature. But it is pretended that some causes are ne- 
cessary, some not necessary. Here then is the ad- 
vantage of definitions. Let any one define a cause, 
without comprehending, as a part of the definition, a 
necessary connexion with its effect ; and let him show 
distinctly the origin of the idea, expressed by the defi- 
nition ; and I shall readily give up the whole contro- 
versy. But if the foregoing explication of the matter 
be received, this must be absolutely impracticable. 
Had not objects a regular conjunction with each other, 
we should never have entertained any notion of cause 
and effect; and this regular conjunction produces that 
inference of the understanding, which is the only con- 
nexion, that we can have any comprehension of. 
Whoever attempts a definition of cause, exclusive of 



ioo AN ENQUIRY CONCERNING 

these circumstances, will be obliged either to employ 
unintelligible terms or such as are synonymous to 
the term which he endeavours to define. 1 And if the 
definition above mentioned be admitted ; liberty, when 
opposed to necessity, not to constraint, is the same 
thing with chance ; which is universally allowed to 
have no existence. 

Part II. 

There is no method of reasoning more common, 
and yet none more blameable, than, in philosophical 
disputes, to endeavour the refutation of any hypothe- 
sis, by a pretence of its dangerous consequences to 
religion and morality. When any opinion leads to 
absurdities, it is certainly false ; but it is not certain 
that an opinion is false, because it is of dangerous 
consequence. Such topics, therefore, ought entirely 
to be forborne ; as serving nothing to the discov- 
ery of truth, but only to make the person of an antag- 
onist odious. This I observe in general, without 
pretending to draw any advantage from it. I frankly 
submit to an examination of this kind, and shall ven- 
ture to affirm that the doctrines, both of necessity and 
of liberty, as above explained, are not only consistent 
with morality, but are absolutely essential to its 
support. 

Necessity may be defined two ways, conformably 

1 Thus, if a cause be denned, that which produces any thing; it is easy to 
observe, that producing is synonimous to causing. In like manner, if a cause 
be defined, that by which any thing exists; this is liable to the same objec- 
tion. For what is meant by these words, by which ? Had it been said, that a 
cause is that after which any thing constantly exists ; we should have under- 
stood the terms. For this is, indeed, all we know of the matter. And this 
constancy forms the very essence of necessity, nor have we any other idea 
of it. 



HUMAN UNDERSTANDING. ior 

to the two definitions of cause, of which it makes an 
essential part. It consists either in the constant 
conjunction of like objects, or in the inference of the 
understanding from one object to another. Now ne- 
cessity, in both these senses, (which, indeed, are at 
bottom the same) has universally, though tacitly, in 
the schools, in the pulpit, and in common life, been 
allowed to belong to the will of man ; and no one has 
ever pretended to deny that we can draw inferences 
concerning human actions, and that those inferences 
are founded on the experienced union of like actions, 
with like motives, inclinations, and circumstances. 
The only particular in which any one can differ, is, 
that either, perhaps, he will refuse to give the name 
of necessity to this property of hum^in actions: But 
as long as the meaning is understood, I hope the word 
can do no harm : Or that he will m lintain it possible 
to discover something farther in the operations of 
matter. But this, it must be acknowledged, can be 
of no consequence to morality or religion, whatever it 
may be to natural philosophy or metaphysics. We 
may here be mistaken in asserting that there is no idea 
of any other necessity or connexion in the actions of 
body : But surely we ascribe nothing to the actions 
of the mind, but what everyone does, and must readily 
allow of. We change no circumstance in the received 
orthodox system with regard to the will, but only in 
that with regard to material objects and causes. Noth- 
ing, therefore, can be more innocent, at least, than 
this doctrine. 

All laws being founded on rewards and punish- 
ments, it is supposed as a fundamental principle, that 
these motives have a regular and uniform influence on 
the mind, and both produce the good and prevent the 



162 AN enq uir y ^CONCERNING 

evil actions. We may give to this influence what 
name we please ; but, as it is usually conjoined with 
the action, it must be esteemed a cause, and be looked 
upon as an instance of that necessity, which we would 
here establish. 

The only proper object of hatred or vengeance is 
a person or creature, endowed with thought and con- 
sciousness; and when any criminal or injurious ac- 
tions excite that passion, it is only by their relation to 
the person, or connexion with him. Actions are, by 
their very nature, temporary and perishing ; and 
where they proceed not from some cause in the char- 
acter and disposition of the person who performed 
them, they can neither redound to his honour, if good; 
nor infamy, if eyil. The actions themselves may be 
blameable; they may be contrary to all the rules of 
morality and religion : But the person is not answer- 
able for them ; and as they proceeded from nothing in 
him that is durable and constant, and leave nothing 
of that nature behind them, it is impossible he can, 
upon their account, become the object of punishment 
or vengeance. According to the principle, therefore, 
which denies necessity, and consequently causes, a 
man is as pure and untainted, after having committed 
the most horrid crime, as at the first moment of his 
birth, nor is his character anywise concerned in his 
actions, since they are not derived from it, and the 
wickedness of the one can never be used as a proof of 
the depravity of the other. 

Men are not blamed for such actions as they per- 
form ignorantly and casually, whatever may be the 
consequences. Why ? but because the principles of 
these actions are only momentary, and terminate in 
them alone. Men are less blamed for such actions as 






HUMAN UNDERSTANDING. 103 

they perform hastily and unpremeditately than for such 
as proceed from deliberation. For what reason ? but 
because a hast)' temper, though a constant cause or 
principle in the mind, operates only by intervals, and 
infects not the whole character. Again, repentance 
wipes off every crime, if attended with a reformation 
of life and manners. How is this to be accounted for? 
but by asserting that actions render a person criminal 
merely as they are proofs of criminal principles in the 
mind ; and when, by an alteration of these principles, 
they cease to be just proofs, they likewise cease to be 
zriminal. But, except upon the doctrine of necessity, 
they never were just proofs, and consequently never 
were criminal. 

It will be equally easy to prove, and from the same 
arguments, that liberty, according to that definition 
above mentioned, in which all men agree, is also es- 
sential to morality, and that no human actions, where 
it is wanting, are susceptible of any moral qualities, 
or can be the objects either of approbation or dislike. 
For as actions are objects of our moral sentiment, so 
far only as they are indications of the internal char- 
acter, passions, and affections ; it is impossible that 
they can give rise either to praise or blame, where 
they proceed not from these principles, but are derived 
altogether frem external violence. 

I pretend not to have obviated or removed all ob- 
jections to this theory, with regard to necessity and 
liberty. I can foresee other objections, derived from 
topics which have not here been treated of. It may 
be said, for instance, that, if voluntary actions be sub- 
jected to the same laws of necessity with the operations 
of matter, there is a continued chain of necessary 
causes, pre-ordained and pre-determined, reaching 



io 4 AN ENQUIRY CONCERNING 

from the original cause of all to every single volition 
of every human creature. No contingency anywhere 
in the universe ; no indifference ; no liberty. While 
we act, we are, at the same time, acted upon. The 
ultimate Author of all our volitions is the Creator of 
the world, who first bestowed motion on this immense 
machine, and placed all beings in that particular 
position, whence every subsequent event, by an in- 
evitable necessity, must result. Human actions, 
therefore, either can have no moral turpitude at all, as 
proceeding from so good a cause ; or if they have any 
turpitude, they must involve our Creator in the same 
guilt, while he is acknowledged to be their ultimate 
cause and author. For as a man, who fired a mine, 
is answerable for all the consequences whether the 
train he employed be long or short ; so wherever a 
continued chain of necessary causes is fixed, that Be- 
ing, either finite or infinite, who produces the first, is 
likewise the author of all the rest, and must both bear 
the blame and acquire the praise which belong to them. 
Our clear and unalterable ideas of morality establish 
this rule, upon unquestionable reasons, when we ex- 
amine the consequences of any human action ; and 
these reasons must still have greater force when ap- 
plied to the volitions and intentions of a Being infi- 
nitely wise and powerful. Ignorance or impotence 
may be pleaded for so limited a creature as man ; but 
those imperfections have no place in our Creator. He 
foresaw, he ordained, he intended all those actions of 
men, which we so rashly pronounce criminal. And we 
must therefore conclude, either that they are not crim- 
inal, or that the Deity, not man, is accountable for 
them. But as either of these positions is absurd and 
impious, it follows, that the doctrine from which they 



HUMAN UNDERSTANDING 105 

are deduced cannot possibly be true, as being liable 
to all the same objections. An absurd consequence, 
if necessary, proves the original doctrine to be absurd ; 
in the same manner as criminal actions render crim- 
inal the original cause, if the connexion between them 
be necessary and evitable. 

This objection consists of two parts, which we shall 
examine separately; First, that, if human actions can 
be traced up, by a necessary chain, to the Deity, they 
can never be criminal ; on account of the infinite per- 
fection of that Being from whom they are derived, 
and who can intend nothing but what is altogether 
good and laudable. Or, Secondly, if they be criminal, 
we must retract the attribute of perfection, which we 
ascribe to the Deity, and must acknowledge him to 
be the ultimate author of guilt and moral turpitude in 
all his creatures. 

The answer to the first objection seems obvious 
and convincing. There are many philosophers who, 
after an exact scrutiny of all the phenomena of nature, 
conclude, that the whole, considered as one system, 
is, in every period of its existence, ordered with per- 
fect benevolence; and that the utmost possible happi- 
ness will, in the end, result to all created beings, with- 
out any mixture of positive or absolute ill or misery. 
Every physical ill, say they, makes an essential part 
of this benevolent system, and could not possibly be 
removed, even by the Deity himself, considered as a 
wise agent, without giving entrance to greater ill, or 
excluding greater good, which will result from it. 
From this theory, some philosophers, and the ancient 
Stoics among the rest, derived a topic of consolation 
under all afflictions, while they taught their pupils 
that those ills under which they laboured were, in real- 



io6 AN ENQ UIR V CONCERNING 

ity, goods to the universe ; and that to an enlarged 
view, which could comprehend the whole system of 
nature, every event became an object of joy and exul- 
tation. But though this topic be specious and sub- 
lime, it was soon found in practice weak and ineffec- 
tual. You would surely more irritate than appease a 
man lying under the racking pains of the gout by 
preaching up to him the rectitude of those general 
laws, which produced the malignant humours in his 
body, and led them through the proper canals, to the 
sinews and nerves, where they now excite such acute 
torments. These enlarged views may, for a moment, 
please the imagination of a speculative man, who is 
placed in ease and security; but neither can they dwell 
with constancy on his mind, even though undisturbed 
by the emotions of pain or passion ; much less can 
they maintain their ground when attacked by such 
powerful antagonists. The affections take a narrower 
and more natural survey of their object ; and by an 
economy, more suitable to the infirmity of human 
minds, regard alone the beings around us, and are 
actuated by such events as appear good or ill to the 
private system. 

The case is the same with moral as with physical ill. 
It cannot reasonably be supposed, that those remote 
considerations, which are found of so little efficacy 
with regard to one, will have a more powerful influ- 
ence with regard to the other. The mind of man is 
so formed by nature that, upon the appearance of cer- 
tain characters, dispositions, and actions, it immedi- 
ately feels the sentiment of approbation or blame; nor 
are there any emotions more essential to its frame and 
constitution. The characters which engage our ap- 
probation are chiefly such as contribute to the peace 



HUMAN UNDERSTANDING. 107 

and security of human society; as the characters which 
excite blame are chiefly such as tend to public detri- 
ment and disturbance : Whence it may reasonably be 
presumed, that the moral sentiments arise, either me- 
diately or immediately, from a reflection of these op- 
posite interests. What though philosophical medita- 
tions establish a different opinion or conjecture ; that 
everything is right with regard to the whole, and that 
the qualities, which disturb society, are, in the main, 
as beneficial, and are as suitable to the primary in- 
tention of nature as those which more directly pro- 
mote its happiness and welfare? Are such remote and 
uncertain speculations able to counterbalance the sen- 
timents which arise from the natural and immediate 
view of the objects? A man who is robbed of a con- 
siderable sum ; does he find his vexation for the loss 
anywise diminished by these sublime reflections? Why 
then should his moral resentment against the crime 
be supposed incompatible with them? Or why should 
not the acknowledgment of a real distinction between 
vice and virtue be reconcileable to all speculative sys- 
tems of philosophy, as well as that of a real distinction 
between personal beauty and deformity? Both these 
distinctions are founded in the natural sentiments of 
the human mind: And these sentiments are not to 
be controuled or altered by any philosophical theory 
or speculation whatsoever. 

The second objection admits not of so easy and sat- 
isfactory an answer ; nor is it possible to explain dis- 
tinctly, how the Deity can be the mediate cause of all 
the actions of men, without being the author of sin 
and moral turpitude. These are mysteries, which mere 
natural and unassisted reason is very unfit to handle ; 
and whatever system she embraces, she must fi*id her- 



io8 

self involved in inextricable difficulties, and even con- 
tradictions, at every step which she takes with regard 
to such subjects. To reconcile the indifference and 
contingency of human actions with prescience; or to 
defend absolute decrees, and yet free the Deity from 
being the author of sin, has been found hitherto to ex- 
ceed all the power of philosophy. Happy, if she be 
thence sensible of her temerity, when she pries into 
these sublime mysteries ; and leaving a scene so full 
of obscurities and perplexities, return, with suitable 
modesty, to her true and proper province, the exami- 
nation of common life; where she will find difficulties 
enough to employ her enquiries, without launching 
into so boundless an ocean of doubt, uncertainty, and 
contradiction ! 



SECTION IX. 

OF THE REASON OF ANIMALS 

ALL our reasonings concerning matter of fact are 
JTx. founded on a species of Analogy, which leads us 
to expect from any cause the same events, which we 
have observed to result from similar causes. Where 
the causes are entirely similar, the analogy is perfect, 
and the inference, drawn from it, is regarded as cer- 
tain and conclusive: nor does any man ever entertain 
a doubt, when he sees a piece of iron, that it will have 
weight and cohesion of parts; as in all other instances, 
which have ever fallen under his observation. But 
where the objects have not so exact a similarity, the 
analogy is less perfect, and the inference is less con- 
clusive ; though still it has some force, in proportion 
to the degree of similarity and resemblance. The ana- 
tomical observations, formed upon one animal, are, 
by this species of reasoning, extended to all animals; 
and it is certain, that when the circulation of the blood, 
for instance, is clearly proved to have place in one 
creature, as a frog, or fish, it forms a strong presump- 
tion, that the same principle has place in all. These 
analogical observations may be carried farther, even 
to this science, of which we are now treating; and 
any theory, by which we explain the operations of the 
understanding, or the origin and connexion of the 
passions in man, will acquire additional authority, if 
we find, that the same theory is requisite to explain 



1 10 AN ENQ UIR Y CONCERNING 

the same phenomena in all other animals. We shall 
make trial of this, with regard to the hypothesis, by 
which we have, in the foregoing discourse, endeav- 
oured to account for all experimental reasonings; and 
it is hoped, that this new point of view will serve to 
confirm all our former observations. 

First, It seems evident, that animals as well as men 
learn many things from experience, and infer, that the 
same events will always follow from the same causes. 
By this principle they become acquainted with the 
more obvious properties of external objects, and grad- 
ually, from their birth, treasure up a knowledge of the 
nature of fire, water, earth, stones, heights, depths, 
&c, and of the effects which result from their opera- 
tion. The ignorance and inexperience of the young 
are here plainly distinguishable from the cunning and 
sagacity of the old, who have learned, by long obser- 
vation, to avoid what hurt them, and to pursue what 
gave ease or pleasure. A horse, that has been accus- 
tomed to the field, becomes acquainted with the proper 
height which he can leap, and will never attempt what 
exceeds his force and ability. An old greyhound will 
trust the more fatiguing part of the chace to the 
younger, and will place himself so as to meet the hare 
in her doubles; nor are the conjectures, which he 
forms on this occasion, founded in any thing but his 
observation and experience. 

This is still more evident from the effects of disci- 
pline and education on animals, who, by the proper 
application of rewards and punishments, may be taught 
any course of action, and most contrary to their natu- 
ral instincts and propensities. Is it not experience, 
which renders a dog apprehensive of pain, when you 
menace him, or lift up the whip to beat him ? Is it 



HUMAN UNDERSTANDING. in 

not even experience, which makes him answer to his 
name, and infer, from such an arbitrary sound, that 
you mean him rather than any of his fellows, and in- 
tend to call him, when you pronounce it in a certain 
manner, and with a certain tone and accent? 

In all these cases, we may observe, that the animal 
infers some fact beyond what immediately strikes his 
senses ; and that this inference is altogether founded 
on past experience, while the creature expects from 
the present object the same consequences, which it has 
always found in its observation to result from similar 
objects. 

Secondly, It is impossible, that this inference of the 
animal can be founded on any process of argument or 
reasoning, by which he concludes, that like events 
must follow like objects, and that the course of nature 
will always be regular in its operations. For if there 
be in reality any arguments of this nature, they surely 
lie too abstruse for the observation of such imperfect 
understandings ; since it may well employ the utmost 
care and attention of a philosophic genius to discover 
and observe them. Animals, therefore, are not guided 
in these inferences by reasoning : Neither are chil- 
dren : Neither are the generality of mankind, in their 
ordinary actions and conclusions : Neither are philos- 
ophers themselves, who, in all the active parts of life, 
are, in the main, the same with the vulgar, and are 
governed by the same maxims. Nature must have 
provided some other principle, of more ready, and 
more general use and application ; nor can an opera- 
tion of such immense consequence in life, as that of 
inferring effects from causes, be trusted to the uncer- 
tain process of reasoning and argumentation. Were 
this doubtful with regard to men, it seems to admit of 



ii2 AN ENQUIRY CONCERNING 

no question with regard to the brute creation ; and 
the conclusion being once firmly established in the 
one, we have a strong presumption, from all the rules 
of analogy, that it ought to be universally admitted, 
without any exception or reserve. It is custom alone, 
which engages animals, from every object, that strikes 
their senses, to infer its usual attendant, and carries 
their imagination, from the appearance of the one, to 
conceive the other, in that particular manner, which 
we denominate belief. No other explication can be 
given of this operation, in all the higher, as well as 
lower classes of sensitive beings, which fall under our 
notice and observation. 1 

1 Since all reasonings concerning facts or causes is derived merely from 
custom, it may be asked how it happens, that men so much surpass animals 
in reasoning, and one man so much surpasses another? Has not the same 
custom the same influence on all? 

We shall here endeavour briefly to explain the great difference in human 
understandings: After which the reason of the difference between men and 
animals will easily be comprehended. 

i. When we have lived any time, and have been accustomed to the uni- 
formity of nature, we acquire a general habit, by which we always transfer 
the known to the unknown, and conceive the latter to resemble the former. 
By means of this general habitual principle, we regard even one experiment 
as the foundation of reasoning, and expect a similar event with some degree 
of certainty, where the experiment has been made accurately, and free from 
all foreign circumstances. It is therefore considered as a matter of great 
importance to observe the consequences of things; and as one man may very 
much surpass another in attention and memory and observation, this will 
make a very great difference in their reasoning. 

2. Where there is a complication of causes to produce any effect, one 
mind may be much larger than another, and better able to comprehend the 
whole system of objects, and to infer justly their consequences. 

3. One man is able to carry on a chain of consequences to a greater 
length than another. 

4. Few men can think long without running into a confusion of ideas, 
and mistaking one for another; and there are various degrees of this in- 
firmity. 

5. The circumstance, on which the effect depends, is frequently involved 
in other circumstances, which are foreign and extrinsic. The separation of 
it often requires great attention, accuracy, and subtilty. 

6. The forming of general maxims from particular observation is a very 
nice operation ; and nothing is more usual, from haste or narrowness of mind 
which sees not on all sides, than to commit mistakes in this particular. 



HUMAN UNDERSTANDING. 113 

But though animals learn many parts of their 
knowledge from observation, there are also many parts 
of it, which they derive from the original hand of nature; 
which much exceed the share of capacity they possess 
on ordinary occasions ; and in which they improve, 
little or nothing, by the longest practice and experi- 
ence. These we denominate Instincts, and are so apt 
to admire as something very extraordinary, and inexpli- 
cable by all the disquisitions of human understanding. 
But our wonder will, perhaps, cease or diminish, whei 
we consider, that the experimental reasoning itself, 
which we possess in common with beasts, and en 
which the whole conduct of life depends, is nothing 
but a species of instinct or mechanical power, that 
acts in us unknown to ourselves ; and in its chief op- 
erations, is not directed by any such relations or com- 
parisons of ideas, as are the proper objects of our in- 
tellectual faculties. Though the instinct be different, 
yet still it is an instinct, which teaches a man to avoid 
the fire ; as much as that, which teaches a bird, with 
such exactness, the art of incubation, and the whole 
economy and order of its nursery. 

7. When we reason from analogies, the man, who has the greater expe- 
rience or the greater promptitude of suggesting analogies, will be the better 
reasoner. 

8. Byasses from prejudice, education, passion, party, &c, hang more 
upon one mind than another. 

9. After we have acquired a confidence in human testimony, books and 
conversation enlarge much more the sphere of one mans experience and 
thought than those of another. 

It would be easy to discover many other circumstances that make a dif- 
ference in the understandings of men. 



SECTION X 

OF MIRACLES. 

Part I. 

THERE is, in Dr. Tillotson's writings, an argument 
against the real presence, which is as concise, and 
elegant, and strong as any argument can possibly be 
supposed against a doctrine, so little worthy of a seri- 
ous refutation. It is acknowledged on all hands, says 
that learned prelate, that the authority, either of the 
scripture or of tradition, is founded merely in the tes- 
timony of the apostles, who were eye-witnesses to 
those miracles of our Saviour, by which he proved his 
divine mission. Our evidence, then, for the truth of 
the Christian religion is less than the evidence for the 
truth of our senses ; because, even in the first authors 
of our religion, it was no greater; and it is evident it 
must diminish in passing from them to their disciples; 
nor can any one rest such confidence in their testi- 
mony, as in the immediate object of his senses. But 
a weaker evidence can never destroy a stronger; and 
therefore, were the doctrine of the real presence ever 
so clearly revealed in scripture, it were directly con- 
trary to the rules of just reasoning to give our assent 
to it. It contradicts sense, though both the scripture 
and tradition, on which it is supposed to be built, 
carry not such evidence with them as sense; when they 
are considered merely as external evidences, and are 



HUMAN UNDERSTANDING. 115 

not brought home to everyone's breast, by the imme- 
diate operation of the Holy Spirit. 

Nothing is so convenient as a decisive argument of 
this kind, which must at least silence the most arrogant 
bigotry and superstition, and free us from their imper- 
tinent solicitations. I flatter myself, that I have dis- 
covered an argument of a like nature, which, if just, 
will, with the wise and learned, be an everlasting check 
to all kinds of superstitious delusion, and conse- 
quently, will be useful as long as the world endures. 
For so long, I presume, will the accounts of miracles 
and prodigies be found in all history, sacred and pro- 
fane. 

Though experience be our only guide in reasoning 
concerning matters of fact ; it must be acknowledged, 
that this guide is not altogether infallible, but in some 
cases is apt to lead us into errors. One, who in our 
climate, should expect better weather in any week of 
June than in one of December, would reason justly, 
and conformably to experience ; but it is certain, that 
he may happen, in the event, to find himself mistaken. 
However, we may observe, that, in such a case, he 
would have no cause to complain of experience ; be- 
cause it commonly informs us beforehand of the un- 
certainty, by that contrariety of events, which we may 
learn from a diligent observation. All effects follow 
not with like certainty from their supposed causes. 
Some events are found, in all countries and all ages, 
to have been constantly conjoined together : Others 
are found to have been more variable, and sometimes 
to disappoint our expectations; so that, in our reason- 
ings concerning matter of fact, there are all imaginable 
degrees of assurance, from the highest certainty to the 
lowest species of moral evidence. 



1 16 AN ENQ UIR Y CONCERNING 

A wise man, therefore, proportions his belief to the 
evidence. In such conclusions as are founded on an 
infallible experience, he expects the event with the last 
degree of assurance, and regards his past experience 
as a full proof of the future existence of that event. 
In other cases, he proceeds with more caution : He 
weighs the opposite experiments : He considers 
which side is supported by the greater number of ex- 
periments : to that side he inclines, with doubt and 
hesitation ; and when at last he fixes his judgement, 
the evidence exceeds not what we properly call prob- 
ability. All probability, then, supposes an opposition 
of experiments and observations, where the one side 
is found to overbalance the other, and to produce a 
degree of evidence, proportioned to the superiority. 
A hundred instances or experiments on one side, and 
fifty on another, afford a doubtful expectation of any 
event ; though a hundred uniform experiments, with 
only one that is contradictory, reasonably begets a 
pretty strong degree of assurance. In all cases, we 
must balance the opposite experiments, where they 
are opposite, and deduct the smaller number from the 
greater, in order to know the exact force of the supe- 
rior evidence. 

To apply these principles to a particular instance ; 
we may observe, that there is no species of reasoning 
more common, more useful, and even necessary to 
human life, than that which is derived from the testi- 
mony of men, and the reports of eye-witnesses and 
spectators. This species of reasoning, perhaps, one 
may deny to be founded on the relation of cause and 
effect. I shall not dispute about a word. It will be 
sufficient to observe that our assurance in any argu- 
ment of this kind is derived from no other principle 



HUMAN UNDERSTANDING. 117 

than our observation of the veracity of human testi- 
mony, and of the usual conformity of facts to the re- 
ports of witnesses. It being a general maxim, that 
no objects have any discoverable connexion together, 
and that all the inferences, which we can draw from 
one to another, are founded merely on our experience 
of their constant and regular conjunction ; it is evi- 
dent, that we ought not to make an exception to this 
maxim in favour of human testimony, whose connexion 
with any event seems, in itself, as little necessary as 
any other. Were not the memory tenacious to a cer- 
tain degree; had not men commonly an inclination to 
truth and a principle of probity, were they not sensible 
to shame, when detected in a falsehood : Were not 
these, I say, discovered by experience to be qualities, 
inherent in human nature, we should never repose the 
least confidence in human testimony. A man deliri- 
ous, or noted for falsehood and villany, has no manner 
of authority with us. 

And as the evidence, derived from witnesses and 
human testimony, is founded on past experience, so it 
varies with the experience, and is regarded either as 
proof ox a probability, according as the conjunction be- 
tween any particular kind of report and any kind of 
object has been found to be constant or variable. 
There are a number of circumstances to be taken into 
consideration in all judgements of this kind ; and the 
ultimate standard, by which we determine all disputes, 
that may arise concerning them, is always derived from 
experience and observation. Where this experience 
is not entirely uniform on any side, it is attended with 
an unavoidable contrariety in our judgements, and 
with the same opposition and mutual destruction of 
argument as in every other kind of evidence. We fre- 



n8 AN ENQUIRY CONCERNING 

quently hesitate concerning the reports of others. We 
balance the opposite circumstances, which cause any 
doubt or uncertainty; and when we discover a superi- 
ority on one side, we incline to it; but still with a 
diminution of assurance* in proportion to the force of 
its antagonist. 

This contrariety of evidence, in the present case, 
may be derived from several different causes; from the 
opposition of contrary testimony; from the character 
or number of the witnesses; from the manner of their 
delivering their testimony; or from the union of all 
these circumstances. We entertain a suspicion con- 
cerning any matter of fact, when the witnesses con- 
tradict each other ; when they are but few, or of a 
doubtful character; when they have an interest in 
what they affirm ; when they deliver their testimony 
with hesitation, or on the contrary, with too violent 
asseverations. There are many other particulars of 
the same kind, which may diminish or destroy the 
force of any argument, derived from human testimony. 

Suppose, for instance, that the fact, which the tes- 
timony endeavours to establish, partakes of the extra- 
ordinary and the marvellous; in that case, the evidence, 
resulting from the testimony, admits of a diminution, 
greater or less, in proportion as the fact is more or less 
unusual. The reason why we place any credit in wit- 
nesses and historians, is not derived from any connex- 
ion, which we perceive a priori, between testimony and 
reality, but because we are accustomed to find a con- 
formity between them. But when the fact attested is 
such a one as has seldom fallen under our observation, 
here is a contest of two opposite experiences; of which 
the one destroys the other, as far as its force goes, 
and the superior can only operate on the mind by the 






HUMAN UNDERSTANDING. 119 

force, which remains. The very same principle of 
experience, which gives us a certain degree of assur- 
ance in the testimony of witnesses, gives us also, in 
this case, another degree of assurance against the fact, 
which they endeavour to establish; from which contra- 
diction there necessarily arises a counterpoize, and 
mutual destruction of belief and authority. 

/ should not believe such a story were it told me by 
Cato 9 was a proverbial saying in Rome, even during 
the lifetime of that philosophical patriot. 1 The in- 
credibility of a fact, it was allowed, might invalidate 
so great an authority. 

The Indian prince, who refused to believe the first 
relations concerning the effects of frost, reasoned justly; 
and it naturally required very strong testimony to en- 
gage his assent to facts, that arose from a state of 
nature, with which he was unacquainted, and which 
bore so little analogy to those events, of which he had 
had constant and uniform experience. Though they 
were not contrary to his experience, they were not 
conformable to it. 2 

1 Plutarch, in vita Catonis. 

2 No Indian, it is evident, could have experience that water did not freeze 
in cold climates. This is placing nature in a situation quite unknown to him; 
and it is impossible for him to tell a priori what will result from it. It is 
making a new experiment, the consequence of which is always uncertain. 
One may sometimes conjecture from analogy what will follow ; but still this 
is but conjecture. And it must be confessed, that, in the present case of 
freezing, the event follows contrary to the rules of analogy, and is such as a 
rational Indian would not look for. The operations of cold upon water are 
not gradual, according to the degrees of cold ; but whenever it comes to the 
freezing point, the water passes in a moment, from the utmost liquidity to 
perfect hardness. Such an event, therefore, may be denominated extraordi- 
nary ', and requires a pretty strong testimony, to render it credible to people 
in a warm climate: But still it is not -miraculous, nor contrary to uniform ex- 
perience of the course of nature in cases where all the circumstances are the 
same. The inhabitants of Sumatra have always seen water fluid in their own 
climate, and the freezing of their rivers ought to be deemed a prodigy: But 
they never saw water in Muscovy during the winter; and therefore they can- 
not reasonably be positive what would there be the consequence. 



120 AN ENQ UIR Y CONCERNING 

But in order to encrease the probability against 
the testimony of witnesses, let us suppose, that the 
fact, which they affirm, instead oi being only marvel- 
lous, is really miraculous; and suppose also, that the 
testimony considered apart and in itself, amounts to 
an entire proof; in that case, there is proof against 
proof, of which the strongest must prevail, but still 
with a diminution of its force, in proportion to that of 
its antagonist. 

A miracle is a violation of the laws of nature ; and 
as a firm and unalterable experience has established 
these laws, the proof against a miracle, from the very 
nature of the fact, is as entire as any argument from 
experience can possibly be imagined. Why is it more 
than probable, that all men must die ; that lead can- 
not, of itself, remain suspended in the air ; that fire 
consumes wood, and is extinguished by water ; unless 
it be, that these events are found agreeable to the laws 
of nature, and there is required a violation of these 
laws, or in other words, a miracle to prevent them ? 
Nothing is esteemed a miracle, if it ever happen in 
the common course of nature. It is no miracle that a 
man, seemingly in good health, should die on a sud- 
den : because such a kind of death, though more un- 
usual than any other, has yet been frequently observed 
to happen. But it is a miracle, that a dead man should 
come to life ; because that has never been observed in 
any age or country. There must, therefore, be a uni- 
form experience against every miraculous event, other- 
wise the event would not merit that appellation. And 
as a uniform experience amounts to a proof, there is 
here a direct and full proof, from the nature of the fact, 
against the existence of any miracle; nor can such a 






HUMAN UNDERSTANDING. 121 

proof be destroyed, or the miracle rendered credible, 
but by an opposite proof, which is superior. 1 

The plain consequence is (and it is a general maxim 
worthy of our attention), 'That no testimony is suffi- 
cient to establish a miracle, unless the testimony be 
of such a kind, that its falsehood would be more mi- 
raculous, than the fact, which it endeavours to estab- 
lish ; and even in that case there is a mutual destruc- 
tion of arguments, and the superior only gives us an 
assurance suitable to that degree of force, which re- 
mains, after deducting the inferior.' When anyone 
tells me, that he saw a dead man restored to life, I 
immediately consider with myself, whether it be more 
probable, that this person should either deceive or be 
deceived, or that the fact, which he relates, should 
really have happened. I weigh the one miracle against 
the other ; and according to the superiority, which I 
discover, I pronounce my decision, and always reject 
the greater miracle. If the falsehood of his testimony 
would be more miraculous, than the event which he 



1 Sometimes an event may not, in itself, seem to be contrary to the laws 
of nature, and yet, if it were real, it might, by reason of some circumstances, 
be denominated a miracle; because, in fact, it is contrary to these laws. 
Thus if a person, claiming a divine authority, should command a sick person 
to be well, a healthful man to fall down dead, the clouds to pour rain, the 
winds to blow, in short, should order many natural events, which immediately 
follow upon his command ; these might justly be esteemed miracles, because 
they are really, in this case, contrary to the laws of nature. For if any suspi- 
cion remain, that the event and command concurred by accident, there is no 
miracle and no transgression of the laws of nature. If this suspicion be re- 
moved, there is evidently a miracle, and a transgression of these laws; be- 
cause nothing can be more contrary to nature than that the voice or command 
of a man should have such an influence. A miracle may be accurately defined, 
a transgression of a law of nature by a particular volition of the Deity, or by 
the interposition of some invisible agent. A miracle may either be discoverable 
by men or not. This alters not its nature and essence. The raising of a 
house or ship into the air is a visible miracle. The raising of a feather, when 
the wind wants ever so little of a force requisite for that purpose, is as real a 
miracle, though not so sensible with regard to us. 



122 AN ENQ UIE Y CONCERNING 

relates ; then, and not till then, can he pretend to 
command my belief or opinion. 

Part II. 

In the foregoing reasoning we have supposed, that 
the testimony, upon which a miracle is founded, may 
possibly amount to an entire proof, and that the false- 
hood of that testimony would be a real prodigy: But 
it is easy to shew, that we have been a great deal too 
liberal in our concession, and that there never was a 
miraculous event established on so full an evidence. 

For first, there is not to be found, in all history, 
any miracle attested by a sufficient number of men, of 
such unquestioned good-sense, education, and learn- 
ing, as to secure us against all delusion in themselves; 
of such undoubted integrity, as to place them beyond 
all suspicion of any design to deceive others ; of such 
credit and reputation in the eyes of mankind, as to 
have a great deal to lose in case of their being detected 
in any falsehood; and at the same time, attesting facts 
performed in such a public manner and in so cele- 
brated a part of the world, as to render the detection 
unavoidable : All which circumstances are requisite 
to give us a full assurance in the testimony of men. 

Secondly. We may observe in human nature a prin- 
ciple which, if strictly examined, will be found to di- 
minish extremely the assurance, which we might, from 
human testimony, have, in any kind of prodigy. The 
maxim, by which we commonly conduct ourselves in 
our reasonings, is, that the objects, of which we have 
no experience, resemble those, of which we have; 
that what we have found to be most usual is always 
most probable ; and that where there is an opposition 



HUMAN UNDERSTANDING. 123 

of arguments, we ought to give the preference to such 
as are founded on the greatest number of past obser- 
vations. But though, in proceeding by this rule, we 
readily reject any fact which is unusual and incredible 
in an ordinary degree; yet in advancing farther, the 
mind observes not always the same rule ; but when 
anything is affirmed utterly absurd and miraculous, it 
rather the more readily admits of such a fact, upon 
account of that very circumstance, which ought to de- 
stroy all its authority. The passion of surprise and 
wonder, arising from miracles, being an agreeable emo- 
tion, gives a sensible tendency towards the belief of 
those events, from which it is derived. And this goes 
so far, that even those who cannot enjoy this pleasure 
immediately, nor can believe those miraculous events, 
of which they are informed, yet love to partake of the 
satisfaction at second-hand or by rebound, and place 
a pride and delight in exciting the admiration of others. 
With what greediness are the miraculous accounts 
of travellers received, their descriptions of sea and 
land monsters, their relations of wonderful adventures, 
strange men, and uncouth manners ? But if the spirit 
of religion join itself to the love of wonder, there is an 
end of common sense ; and human testimony, in these 
circumstances, loses all pretensions to authority. A 
religionist may be an enthusiast, and imagine he sees 
what has no reality : he may know his narrative to be 
false, and yet persevere in it, with the best intentions 
in the world, for the sake of promoting so holy a cause: 
or even where this delusion has. not place, vanity, ex- 
cited by so strong a temptation, operates on him more 
powerfully than on the rest of mankind in any other 
circumstances ; and self-interest with equal force. His 
auditors may not have, and commonly have not, suf- 



124 AN EN Q UIR V CONCERNING 

ficient judgement to canvass his evidence: what judge- 
ment they have, they renounce by principle, in these 
sublime and mysterious subjects : or if they were ever 
so willing to employ it, passion and a heated imagina- 
tion disturb the regularity of its operations. Their 
credulity increases his impudence : and his impudence 
overpowers their credulity. 

Eloquence, when at its highest pitch, leaves little 
room for reason or reflection; but addressing itself 
entirely to the fancy or the affections, captivates the 
willing hearers, and subdues their understanding. 
Happily, this pitch it seldom attains. But what a 
Tully or a Demosthenes could scarcely effect over a 
Roman or Athenian audience, every Capuchin, every 
itinerant or stationary teacher can perform over the 
generality of mankind, and in a higher degree, by 
touching such gross and vulgar passions. 

The many instances of forged miracles, and proph- 
ecies, and supernatural events, which, in all ages, 
have either been detected by contrary evidence, or 
which detect themselves by their absurdity, prove 
sufficiently the strong propensity of mankind to the 
extraordinary and the marvellous, and ought reason- 
ably to beget a suspicion against all relations of this 
kind. This is our natural way of thinking, even with 
regard to the most common and most credible events. 
For instance : There is no kind of report which rises 
so easily, and spreads so quickly, especially in country 
places and provincial towns, as those concerning mar- 
riages; insomuch that two young persons of equal 
condition never see each other twice, but the whole 
neighbourhood immediately join them together. The 
pleasure of telling a piece of news so interesting, of 
propagating it, and of being the first reporters of it, 



HUMAN UNDERSTANDING. 125 

spreads the intelligence. And this is so well known, 
that no man of sense gives attention to these reports, 
till he find them confirmed by some greater evidence. 
Do not the same passions, and others still stronger, 
incline the generality of mankind to believe and report, 
with the greatest vehemence and assurance, all reli- 
gious miracles ? 

Thirdly. It forms a strong presumption against 
all supernatural and miraculous relations, that they 
are observed chiefly to abound among ignorant and 
barbarous nations ; or if a civilized people has ever 
given admission to any of them, that people will be 
found to have received them from ignorant and bar- 
barous ancestors, who transmitted them with that in- 
violable sanction and authority, which always attend 
received opinions. When we peruse the first histories 
of all nations, we are apt to imagine ourselves trans- 
ported into some new world ; where the whole frame 
of nature is disjointed, and every element performs its 
operations in a different manner, from what it does at 
present. Battles, revolutions, pestilence, famine and 
death, are never the effect of those natural causes, 
which we experience. Prodigies, omens, oracles, 
judgements, quite obscure the few natural events, that 
are intermingled with them. But as the former grow 
thinner every page, in proportion as we advance nearer 
the enlightened ages, we soon learn, that there is noth- 
ing mysterious or supernatural in the case, but that 
all proceeds from the usual propensity of mankind 
towards the marvellous, and that, though this inclina- 
tion may at intervals receive a check from sense and 
learning, it can never be thoroughly extirpated from 
human nature. 

It is strange^ a judicious reader is apt to say, upon 



126 AN ENQ UIR Y CONCERNING 

the perusal of these wonderful historians, that such 
prodigious events never happen in our days. But it is 
nothing strange, I hope, that men should lie in all 
ages. You must surely have seen instances enough 
of that frailty. You have yourself heard many such 
marvellous relations started, which, being treated with 
scorn by all the wise and judicious, have at last been 
abandoned even by the vulgar. Be assured, that those 
renowned lies, which have spread and flourished to 
such a monstrous height, arose from like beginnings ; 
but being sown in a more proper soil, shot up at last 
into prodigies almost equal to those which they relate. 

It was a wise policy in that false prophet, Alexan- 
der, who though now forgotten, was once so famous, 
to lay the first scene of his impostures in Paphlagonia, 
where, as Lucian tells us, the people were extremely 
ignorant and stupid, and ready to swallow even the 
grossest delusion. People at a distance, who are weak 
enough to think the matter at all worth enquiry, have 
no opportunity of receiving better information. The 
stories come magnified to them by a hundred circum- 
stances. Fools are industrious in propagating the 
imposture ; while the wise and learned are contented, 
in general, to deride its absurdity, without informing 
themselves of the particular facts, by which it may be 
distinctly refuted. And thus the impostor above men- 
tioned was enabled to proceed, from his ignorant 
Paphlagonians, to the enlisting of votaries, even among 
the Grecian philosophers, and men of the most emi- 
nent rank and distinction in Rome : nay, could engage 
the attention of that sage emperor Marcus Aurelius; 
so far as to make him trust the success of a military 
expedition to his deluisve prophecies. 

The advantages are so great, of starting an impos- 






HUMAN" UNDERSTANDING. 127 

ture among an ignorant people, that, even though the 
delusion should be too gross to impose on the gener- 
ality of them {which, though seldom, is sometimes the case) 
it has a much better chance for succeeding in remote 
countries, than if the first scene had been laid in a city 
renowned for arts and knowledge. The most ignorant 
and barbarous of these barbarians carry the report 
abroad. None of their countrymen have a large cor- 
respondence, or sufficient credit and authority to con- 
tradict and beat down the delusion. Men's inclination 
to the marvellous has full opportunity to display itself. 
And thus a story, which is universally exploded in the 
place where it was first started, shall pass for certain 
at a thousand miles distance. But had Alexander 
fixed his residence at Athens, the philosophers of that 
renowned mart of learning had immediately spread, 
throughout the whole Roman empire, their sense of 
the matter ; which, being supported by so great au- 
thority, and displayed by all the force of reason and 
eloquence, had entirely opened the eyes of mankind. 
It is true ; Lucian, passing by chance through Paph- 
lagonia, had an opportunity of performing this good 
office. But, though much to be wished, it does not 
always happen, that every Alexander meets with a 
Lucian, ready to expose and detect his impostures. 

I may add as a. fourth reason, which diminishes the 
authority of prodigies, that there is no testimony for 
any, even those which have not been expressly de- 
tected, that is not opposed by an infinite number of 
witnesses ; so that not only the miracle destroys the 
credit of testimony, but the testimony destroys itself. 
To make this the better understood, let us consider, 
that, in matters of religion, whatever is different is 
contrary; and that it is impossible the religions of 



128 AN ENQUIRY CONCERNING 

ancient Rome, of Turkey, of Siam, and of China 
should, all of them, be established on any solid foun- 
dation. Every miracle, therefore, pretended to have 
been wrought in any of these religions (and all of them 
abound in miracles), as its direct scope is to establish 
the particular system to which it is attributed ; so has 
it the same force, though more indirectly, to overthrow 
every other system. In destroying a rival system, it 
likewise destroys the credit of those miracles, on which 
that system was established ; so that all the prodigies 
of different religions are to be regarded as contrary 
facts, and the evidences of these prodigies, whether 
weak or strong, as opposite to each other. According 
to this method of reasoning, when we believe any mir- 
acle of Mahomet or his successors, we have for our 
warrant the testimony of a .few barbarous Arabians : 
And on the other hand, we are to regard the authority 
of Titus Livius, Plutarch, Tacitus, and, in short, of 
all the authors and witnesses, Grecian, Chinese, and 
Roman Catholic, who have related any miracle in their 
particular religion ; I say, we are to regard their testi- 
mony in the same light as if they had mentioned that 
Mahometan miracle, and had in express terms contra- 
dicted it, with the same certainty as they have for the 
miracle they relate. This argument may appear over 
subtile and refined ; but is not in reality different from 
the reasoning of a judge, who supposes, that the credit 
of two witnesses, maintaining a crime against any one, 
is destroyed by the testimony of two others, who affirm 
him to have been two hundred leagues distant, at the 
same instant when the crime is said to have been com- 
mitted. 

One of the best attested miracles in all profane his- 
tory, is that which Tacitus reports of Vespasian, who 



HUMAN UNDERSTANDING. 129 

cured a blind man in Alexandria, by means of his 
spittle, and a lame man by the mere touch of his foot ; 
in obedience to a vision of the god Serapis, who had 
enjoined them to have recourse to the Emperor, for 
these miraculous cures. The story may be seen in that 
fine historian; 1 where every circumstance seems to 
add weight to the testimony, and might be displayed 
at large with all the force of argument and eloquence, 
if any one were now concerned to enforce the evidence 
of that exploded and idolatrous superstition. The 
gravity, solidity, age, and probity of so great an em- 
peror, who, through the whole course of his life, con- 
versed in a familiar manner with his friends and court- 
iers, and never affected those extraordinary airs of 
divinity assumed by Alexander and Demetrius. The 
historian, a cotemporary writer, noted for candour and 
veracity, and withal, the greatest and most penetrat- 
ing genius, perhaps, of all antiquity; and so free from 
any tendency to credulity, that he even lies under the 
contrary imputation, of atheism and profaneness: The 
persons, from whose authority he related the miracle, 
of established character for judgement and veracity, 
as we may well presume; eye-witnesses of the fact, 
and confirming their testimony, after the Flavian fam- 
ily was despoiled of the empire, and could no longer 
give any reward, as the price of a lie. Utnmique, qui 
interfuere, nunc quoque mcmorant, postquam nullum men- 
dacio pretium. To which if we add the public nature 
of the facts, as related, it will appear, that no evidence 
can well be supposed stronger for so gross and so 
palpable a falsehood. 

There is al%D a memorable story related by Cardi- 

1 Hist. lib. v. cap. 8. Suetonius gives nearly the same account in vita 

Vesp. 



1 30 AN ENQ UIR V CONCERNING 

nal de Retz, which may well deserve our consideration. 
When that intriguing politician fled into Spain, to 
avoid the persecution of his enemies, he passed through 
Saragossa, the capital of Arragon, where he was shewn, 
in the cathedral, a man, who had served seven years 
as a doorkeeper, and was well known to every body in 
town, that had ever paid his devotions at that church. 
He had been seen, for so long a time, wanting a leg; 
but recovered that limb by the rubbing of holy oil upon 
the stump ; and the cardinal assures us that he saw 
him with two legs. This miracle was vouched by all 
the canons of the church ; and the whole company in 
town were appealed to for a confirmation of the fact ; 
whom the cardinal found, by their zealous devotion, 
to be thorough believers of the miracle. Here the 
relater was also cotemporary to the supposed prodigy, 
of an incredulous and libertine character, as well as 
of great genius ; the miracle of so singular a nature as 
could scarcely admit of a counterfeit, and the witnesses 
very numerous, and all of them, in a manner, specta- 
tors of the fact, to which they gave their testimony. 
And what adds mightily to the force of the evidence, 
and may double our surprise on this occasion, is, that 
the cardinal himself, who relates the story, seems not 
to give any credit to it, and consequently cannot be 
suspected of any concurrence in the holy fraud. He 
considered justly, that it was not requisite, in order to 
reject a fact of this nature, to be able accurately to 
disprove the testimony, and to trace its falsehood, 
through all the circumstances of knavery and credulity 
which produced it. He knew, that, as this was com- 
monly altogether impossible at any sm^ll distance of 
time and place; so was it extremely difficult, even 
where one was immediately present, by reason of the 



HUMAN- UNDERSTANDING 131 

bigotry, ignorance, cunning, and roguery of a great 
part of mankind. He therefore concluded, like a just 
reasoner, that such an evidence carried falsehood upon 
the very face of it, and that a miracle, supported by 
any human testimony, was more properly a subject of 
derision than of argument. 

There surely never was a greater number of mir- 
acles ascribed to one person, than those, which were 
lately said to have been wrought in France upon the 
tomb of Abbe* Paris, the famous Jansenist, with whose 
sanctity the people were so long deluded. The curing 
of the sick, giving hearing to the deaf, and sight to 
the blind, were every where talked of as the usual ef- 
fects of that holy sepulchre. But what is more extra- 
ordinary ; many of the miracles were immediately 
proved upon the spot, before judges of unquestioned 
integrity, attested by witnesses of credit and distinc- 
tion, in a learned age, and on the most eminent the- 
atre that is now in the world. Nor is this all : a rela- 
tion of them was published and dispersed everywhere; 
nor were the Jesuits, though a learned body, supported 
by the civil magistrate, and determined enemies to 
those opinions, in whose favour the miracles were said 
to have been wrought, ever able distinctly to refute or 
detect them. Where shall we find such a number of 
circumstances, agreeing to the corroboration of one 
fact? And what have we to oppose to such a cloud 
of witnesses, but the absolute impossibility or miracu- 
lous nature of the events, which they relate ? And this 
surely, in the eyes of all reasonable people, will alone 
be regarded as a sufficient refutation. 

Is the consequence just, because some human tes- 
timony has the utmost force and authority in some 
cases, when it relates the battle of Philippi or Pharsa- 



x 3 a AN ENQUIR Y C ONCE RIVING 

lia for instance ; that therefore all kinds of testimony 
must, in all cases, have equal force and authority? 
Suppose that the Caesarean and Pompeian factions 
had, each of them, claimed the victory in these bat- 
tles, and that the historians of each party had uniformly 
ascribed the advantage to their own side ; how could 
mankind, at this distance, have been able to deter- 
mine between them? The contrariety is equally strong 
between the miracles related by Herodotus or Plutarch, 
and those delivered by Mariana, Bede, or any monkish 
historian. 

The wise lend a very academic faith to every report 
which favours the passion of the reporter; whether it 
magnifies his country, his family, or himself, or in any 
other way strikes in with his natural inclinations and 
propensities. But what greater temptation than to 
appear a missionary, a prophet, an ambassador from 
heaven? Who would not encounter many dangers and 
difficulties, in order to attain so sublime a character? 
Or if, by the help of vanity and a heated imagination, 
a man has first made a convert of himself, and entered 
seriously into the delusion; who ever scruples to make 
use of pious frauds, in support of so holy and merito- 
rious a cause? 

The smallest spark may here kindle into the great- 
est flame ; because the materials are always prepared 
for it. The avidum genus auricularui?i, 1 the gazing 
populace, receive greedily, without examination, what- 
ever soothes superstition, and promotes wonder. 

How many stories of this nature have, in all ages, 
been detected and exploded in their infancy? How 
many more have been celebrated for a time, and have 
afterwards sunk into neglect and oblivion? Where 

l Lucret 



HUMAN UNDERSTANDING. 133 

such reports, therefore, fly about, the solution of the 
phenomenon is obvious; and we judge in conformity 
to regular experience and observation, when we ac- 
count for it by the known and natural principles of 
credulity and delusion. And shall we, rather than 
have a recourse to so natural a solution, allow of a 
miraculous violation of the most established laws of 
nature? 

I need not mention the difficulty of detecting a false- 
hood in any private or even public history, at the 
place, where it is said to happen ; much more when 
the scene is removed to ever so small a distance. 
Even a court of judicature, with all the authority, ac- 
curacy, and judgement, which they can employ, find 
themselves often at a loss to distinguish between truth 
and falsehood in the most recent actions. But the 
matter never comes to any issue, if trusted to the com- 
mon method of altercations and debate and flying ru- 
mours; especially when men's passions have taken part 
on either side. 

In the infancy of new religions, the wise and learned 
commonly esteem the matter too inconsiderable to de- 
serve their attention or regard. And when afterwards 
they would willingly detect the cheat, in order to un- 
deceive the deluded multitude, the season is now 
past, and the records and witnesses, which might 
clear up the matter, have perished beyond recovery. 

No means of detection remain, but those which 
must be drawn from the very testimony itself of tne 
reporters: and these, though always sufficient with 
the judicious and knowing, are commonly too fine to 
fall under the comprehension of the vulgar. 

Upon the whole, then, it appears, that no testi- 
mony for any kind of miracle has ever amounted to a 



t34 AN &XQUIR T CONCERNING 

probability, much less to a proof; and that, even sup- 
posing it amounted to a proof, it would be opposed 
by another proof ; derived from the very nature of the 
fact, which it would endeavour to establish. It is ex- 
perience only, which gives authority to human testi- 
mony; and it is the same experience, which assures us 
of the laws of nature. When, therefore, these two kinds 
of experience are contrary, we have nothing to do 
but substract the one from the other, and embrace 
an opinion, either on one side or the other, with that 
assurance which arises from the remainder. But ac- 
cording to the principle here explained, this substrac- 
tion, with regard to all popular religions, amounts to 
an entire annihilation ; and therefore we may establish 
it as a maxim, that no human testimony can have such 
force as to prove a miracle, and make it a just foun- 
dation for any such system of religion. 

I beg the limitations here made may be remarked, 
when I say, that a miracle can never be proved, so as 
to be the foundation of a system of religion. For I 
own, that otherwise, there may possibly be miracles, 
or violations of the usual course of nature, of such a 
kind as to admit of proof from human testimony; 
though, perhaps, it will be impossible to find any such 
in all the records of history. Thus, suppose, all 
authors, in all languages, agree, that, from the first of 
J anuary 1 600, there was a total darkness over the whole 
earth for eight days: suppose that the tradition of this 
extraordinary event is still strong and lively among 
the people: that all travellers, who return from foreign 
countries, bring us accounts of the same tradition, 
without the least variation or contradiction : it is evi- 
dent, that our present philosophers, instead of doubt- 
ing the fact, ought to receive it as certain, and ought 



HUMAN 1 UNDERSTANDING 135 

to search for the causes whence it might be derived. 
The decay, corruption, and dissolution of nature, is 
an event rendered probable by so many analogies, 
that any phenomenon, which seems to have a tend- 
ency towards that catastrophe, comes within the reach 
of human testimony, if that testimony be very exten- 
sive and uniform. 

But suppose, that all the historians who treat of 
England, should agree, that, on the first of Jan- 
uary 1600, Queen Elizabeth died ; that both before 
and after her death she was seen by her physicians 
and the whole court, as is usual with persons of her 
rank ; that her successor was acknowledged and pro- 
claimed by the parliament ; and that, after being in« 
terred a month, she again appeared, resumed the 
throne, and governed England for three years: I must 
confess that I should be surprised at the concurrence 
of so many odd circumstances, but should not have 
the least inclination to believe so miraculous an event. 
I should not doubt of her pretended death, and of 
those other public circumstances that followed it : I 
should only assert it to have been pretended, and that 
it neither was, nor possibly could be real. You would 
in vain object to me the difficulty, and almost impos- 
sibility of deceiving the world in an affair of such con- 
sequence ; the wisdom and solid judgement of that 
renowned queen ; with the little or no advantage 
which she could reap from so poor an artifice : All 
this might astonish me ; but I would still reply, that 
the knavery and folly of men are such common phe- 
nomena, that I should rather believe the most extraor- 
dinary events to arise from their concurrence, than 
admit of so signal a violation of the laws of nature. 

But should this miracle be ascribed to any new 



1 36 AN ENQ UIR Y CONCERNING 

system of religion ; men, in all ages, have been so 
much imposed on by ridiculous stories of that kind, 
that this very circumstance would be a full proof of a 
cheat, and sufficient, with all men of sense, not only 
to make them reject the fact, but even reject it with- 
out farther examination. Though the Being to whom 
the miracle is ascribed, be, in this case, Almighty, it 
does not, upon that account, become a whit more 
probable ; since it is impossible for us to know the 
attributes or actions of such a Being, otherwise than 
from the experience which we have of his productions, 
in the usual course of nature. This still reduces us 
to past observation, and obliges us to compare the 
instances of the violation of truth in the testimony of 
men, with those of the violation of the laws of nature 
by miracles, in order to judge which of them is most 
likely and probable. As the violations of truth are 
more common in the testimony concerning religious 
miracles, than in that concerning any other matter of 
fact ; this must diminish very much the authority of 
the former testimony, and make us form a general 
resolution, never to lend any attention to it, with 
whatever specious pretence it may be covered. 

Lord Bacon seems to have embraced the same 
principles of reasoning. 'We ought/ says he, 'to 
make a collection or particular history of all monsters 
and prodigious births or productions, and in a word 
of every thing new, rare, and extraordinary in nature. 
But this must be done with the most severe scrutiny, 
lest we depart from truth. Above all, every relation 
must be considered as suspicious, which depends in 
any degree upon religion, as the prodigies of Livy : 
And no less so, every thing that is to be found in the 
writers of natural magic or alchimy, or such authors, 



HUMAN UNDERSTANDING. 137 

who seem> all of them, to have an unconquerable ap- 
petite for falsehood and fable.' x 

I am the better pleased with the method of reason- 
ing here delivered, as I think it may serve to confound 
those dangerous friends or disguised enemies to the 
Christian Religion, who have undertaken to defend it 
by the principles of human reason. Our most holy 
religion is founded on Faith, not on reason ; and it is 
a sure method of exposing it to put it to such a trial 
as it is, by no means, fitted to endure. To make this 
more evident, let us examine those miracles, related 
in scripture ; and not to lose ourselves in too wide a 
field, let us confine ourselves to such as we find in the 
Pentateuch, which we shall examine, according to the 
principles of these pretended Christians, not as the 
word or testimony of God himself, but as the produc- 
tion of a mere human writer and historian. Here then 
we are first to consider a book, presented to us by a 
barbarous and ignorant people, written in an age when 
they were still more barbarous, and in all probability 
long after the facts which it relates, corroborated by 
no concurring testimony, and resembling those fabu- 
lous accounts, which every nation gives of its origin. 
Upon reading this book, we find it full of prodigies 
and miracles. It gives an account of a state of the 
world and of human nature entirely different from the 
present : Of our fall from that state : Of the age of 
man, extended to near a thousand years : Of the de- 
struction of the world by a deluge : Of the arbitrary 
choice of one people, as the favourites of heaven ; and 
that people the countrymen of the author : Of their 
deliverance from bondage by prodigies the most aston- 
ishing imaginable : I desire any one to lay his hand 

1 Nov. Org. lib. ii. aph. 29. 



1 38 AN ENQ UIR Y CONCERNING 

upon his heart, and after a serious consideration de- 
clare, whether he thinks that the falsehood of such a 
book, supported by such a testimony, would be more 
extraordinary and miraculous than all the miracles it 
relates; which is, however, necessary to make it be 
received, according to the measures of probability 
above established. 

What we have said of miracles may be applied, 
without any variation, to prophecies ; and indeed, all 
prophecies are real miracles, and as such only, can be 
admitted as proofs of any revelation. If it did not ex- 
ceed the capacity of human nature to foretell future 
events, it would be absurd to employ any prophecy as 
an argument for a divine mission or authority from 
heaven. So that, upon the whole, we may conclude, 
that the Christian Religion not only was at first attended 
with miracles, but even at this day cannot be believed 
by any reasonable person without one. Mere reason 
is insufficient to convince us of its veracity : And who- 
ever is moved by Faith to assent to it, is conscious of 
a continued miracle in his own person, which subverts 
all the principles of his understanding, and gives him 
a determination to believe what is most contrary to 
custom and experience. 



SECTION XI. 

OF A PARTICULAR PROVIDENCE AND OF A FUTURE 
STATE. 

I WAS lately engaged in conversation with a friend 
who loves sceptical paradoxes ; where, though he 
advanced many principles, of which I can by no means 
approve, yet as they seem to be curious, and to bear 
some relation to the chain of reasoning carried on 
throughout this enquiry, I shall here copy them from 
my memory as accurately as I can, in order to submit 
them to the judgement of the reader. 

Our conversation began with my admiring the sin- 
gular good fortune of philosophy, which, as it requires 
entire liberty above all other privileges, and chiefly 
flourishes from the free opposition of sentiments and 
argumentation, received its first birth in an age and 
country of freedom and toleration, and was never 
cramped, even in its most extravagant principles, by 
any creeds, concessions, or penal statutes. For, except 
the banishment of Protagoras, and the death of Soc- 
rates, which last event proceeded partly from other 
motives, there are scarcely any instances to be met 
with, in ancient history, of this bigotted jealousy, with 
which the present age is so much infested. Epicurus 
lived at Athens to an advanced age, in peace and tran- 
quillity: Epicureans 1 were even admitted to receive 
the sacerdotal character, and to officiate at the altar, 



i 4 o AN ENQUIRY CONCERNING 

in the most sacred rites of the established religion : 
And the public encouragement 1 of pensions and sala. 
ries was afforded equally, by the wisest of all the 
Roman emperors, 2 to the professors of every sect of 
philosophy. How requisite such kind of treatment 
was to philosophy, in her early youth, will easily be 
conceived, if we reflect, that, even at present, when 
she may be supposed more hardy and robust, she bears 
with much difficulty the inclemency of the seasons, 
and those harsh winds of calumny and persecution, 
which blow upon her. 

You admire, says my friend, as the singular good 
fortune of philosophy, what seems to result from the 
natural course of things, and to be unavoidable in 
every age and nation. This pertinacious bigotry, of 
which you complain, as so fatal to philosophy, is 
really her offspring, who, after allying with supersti- 
tion, separates himself entirely from the interest of 
his parent, and becomes her most inveterate enemy 
and persecutor. Speculative dogmas of religion, the 
present occasions of such furious dispute, could not 
possibly be conceived or admitted in the early ages of 
the world; when mankind, being wholly illiterate, 
formed an idea of religion more suitable to their weak 
apprehension, and composed their sacred tenets of 
such tales chiefly as were the objects of traditional 
belief, more than of argument or disputation. After 
the first alarm, therefore, was over, which aroje from 
the new paradoxes and principles of the philosophers; 
these teachers seem ever after, during the ages of 
antiquity, to have lived in great harmony with the es- 
tablished superstition, and to have made a fair parti- 

l Luciani evvovxos. i Luciani and Dio. 



HUM A 1ST UNDERSTANDING 14 1 

tion of mankind between them ; the former claiming 
all the learned and wise, the latter possessing all the 
vulgar and illiterate. 

It seems then, say I, that you leave politics entirely 
out of the question, and never suppose, that a wise 
magistrate can justly be jealous of certain tenets of 
philosophy, such as those of Epicurus, which, denying 
a divine existence, and consequently a providence and 
a future state, seem to loosen, in a great measure, the 
ties of morality, and may be supposed, for that reason, 
pernicious to the peace of civil society. 

I know, replied he, that in fact these persecutions 
never, in any age, proceeded from calm reason, or from 
experience of the pernicious consequences of philos- 
ophy; but arose entirely from passion and prejudice. 
But what if I should advance farther, and assert, that 
if Epicurus had been accused before the people, by 
any of the sycophants or informers of those days, he 
could easily have defended his cause, and proved his 
principles of philosophy to be as salutary as those of 
his adversaries, who endeavoured, with such zeal, to 
expose him to the public hatred and jealousy? 

I wish, said I, you would try your eloquence upon 
so extraordinary a topic, and make a speech for Epi- 
curus, which might satisfy, not the mob of Athens, if 
you will allow that ancient and polite city to have con- 
tained any mob, but the more philosophical part of 
his audience, such as might be supposed capable of 
comprehending his arguments. 

The matter would not be difficult, upon such condi- 
tions, replied he : And if you please, I shall suppose 
myself Epicurus for a moment, and make you stand 
for the Athenian people, and shall deliver you such an 
harangue as will fill all the urn with white beans, and 



i 4 2 AN ENQUIRY CONCERNING 

leave not a black one to gratify the malice of my 
adversaries. 

Very well : Pray proceed upon these suppositions. 

I come hither, O ye Athenians, to justify in your 
assembly what I maintained in my school, and I find 
myself impeached by furious antagonists, instead of 
reasoning with calm and dispassionate enquirers. Your 
deliberations, which of right should be directed to 
questions of public good, and the interest of the com- 
monwealth, are diverted to the disquisitions of spec- 
ulative philosophy; and these magnificent, but per- 
haps fruitless enquiries, take place of your more famil- 
iar but more useful occupations. But so far as in me 
lies, I will prevent this abuse. We shall not here dis- 
pute concerning the origin and government of worlds. 
We shall only enquire how far such questions concern 
the public interest. And if I can persuade you, that 
they are entirely indifferent to the peace of society and 
security of government, I hope that you will presently 
send us back to our schools, there to examine, at lei- 
sure, the question the most sublime, but at the same 
time, the most speculative of all philosophy. 

The religious philosophers, not satisfied with the 
tradition of your forefathers, and doctrine of your 
priests (in which I willingly acquiesce), indulge a rash 
curiosity, in trying how far they can establish religion 
upon the principles of reason; and they thereby excite, 
instead of satisfying, the doubts, which naturally arise 
from a diligent and scrutinous enquiry. They paint, 
in the most magnificent colours, the order, beauty, 
and wise arrangement of the universe; and then ask, 
if such a glorious display of intelligence could proceed 
from the fortuitous concourse of atoms, or if chance 
could produce what the greatest genius can never suf- 






HUMAN 1 UNDERSTANDING. 143 

ficiently admire. I shall not examine the justness of 
this argument. I shall allow it to be as solid as my 
antagonists and accusers can desire. It is sufficient, 
if I can prove, from this very reasoning, that the ques- 
tion is entirely speculative, and that, when, in my phi- 
losophical disquisitions, I deny a providence and a 
future state, I undermine not the foundations of soci- 
ety, but advance principles, which they themselves, 
upon their own topics, if they argue consistently, must 
allow to be solid and satisfactory. 

You then, who are my accusers, have acknowledged, 
that the chief or sole argument for a divine existence 
(which I never questioned) is derived from the order 
of nature ; where there appear such marks of intelli- 
gence and design, that you think it extravagant to as- 
sign for its cause, either chance, or the blind and un- 
guided force of matter. You allow, that this is an 
argument drawn from effects to causes. From the 
order of the work, you infer, that there must have been 
project and forethought in the workman. If you can- 
not make out this point, you allow, that your conclu- 
sion fails ; and you pretend not to establish the con- 
clusion in a greater latitude than the phenomena of 
nature will justify. These are your concessions. I 
desire you to mark the consequences. 

When we infer any particular cause from an effect, 
we must proportion the one to the other, and can never 
be allowed to ascribe to the cause any qualities, but 
what are exactly sufficient to produce the effect. A 
body of ten ounces raised in any scale may serve as a 
proof, that the counterbalancing weight exceeds ten 
ounces ; but can never afford a reason that it exceeds 
a hundred. If the cause, assigned for any effect, be 
not sufficient to produce it, we must either reject that 



i 4 4 AN ENQUIRY CONCERNING 

cause, or add to it such qualities as will give it a just 
proportion to the effect. But if we ascribe to it further 
qualities, or affirm it capable of producing other 
effects, we can only indulge the licence of conjecture, 
and arbitrarily suppose the existence of qualities and 
energies, without reason or authority. 

The same rule holds, whether the cause assigned 
be brute unconscious matter, or a rational intelligent 
being. If the cause be known only by the effect, we 
never ought to ascribe to it any qualities, beyond what 
are precisely requisite to produce the effect : Nor can 
we, by any rules of just reasoning, return back from 
the cause, and infer other effects from it, beyond those 
by which alone it is known to us. No one, merely 
from the sight of one of Zeuxis's pictures, could know, 
that he was also a statuary or architect, and was an 
artist no less skilful in stone and marble than in col- 
ours. The talents and taste, displayed in the partic- 
ular work before us; these we may safely conclude 
the workman to be possessed of. The cause must be 
proportioned to the effect ; and if we exactly and pre- 
cisely proportion it, we shall never find in it any 
qualities, that point farther, or afford an inference 
concerning any other design or performance. Such 
qualities must be somewhat beyond what is merely 
requisite for producing the effect, which we examine. 

Allowing, therefore, the gods to be the authors of 
the existence or order of the universe ; it follows, that 
they possess that precise degree of power, intelligence, 
and benevolence, which appears in their workmanship; 
but nothing farther can ever be proved, except we call 
in the assistance of exaggeration and flattery to supply 
the defects of argument and reasoning. So far as the 
traces of any attributes, at present, appear, so far may 



HUMAN UNDERSTANDING. 145 

we conclude these attributes to exist. The supposition 
of farther attributes is mere hypothesis ; much more 
the supposition, that, in distant regions of space or 
periods of time, there has been, or will be, a more mag- 
nificent display of these attributes, and a scheme of 
administration more suitable to such imaginary vir- 
tues. We can never be allowed to mount up from the 
universe, the effect, to Jupiter, the cause ; and then 
descend downwards, to infer any new effect from that 
cause; as if the present effects alone were not entirely 
worthy of the glorious attributes, which we ascribe to 
that deity. The knowledge of the cause being derived 
solely from the effect, they must be exactly adjusted 
to each other; and the one can never refer to anything 
farther, or be the foundation of any new inference and 
conclusion. 

You find certain phenomena in nature. You seek 
a cause or author. You imagine that you have found 
him. You afterwards become so enamoured of this off- 
spring of your brain, that you imagine it impossible, 
but he must produce something greater and more per- 
fect than the present scene of things, which is so full 
of ill and disorder. You forget, that this superlative 
intelligence and benevolence are entirely imaginary, 
or, at least, without any foundation in reason ; and 
that you have no ground to ascribe to him any quali- 
ties, but what you see he has actually exerted and dis- 
played in his productions. Let your gods, therefore, 
O philosophers, be suited to the present appearances 
of nature: and presume not to alter these appearances 
by arbitrary suppositions, in order to suit them to the 
attributes, which you so fondly ascribe to your deities. 

When priests and poets, supported by your author- 
ity, O Athenians, talk of a golden or silver age, which 



* 4 6 AN ENQUIRY CONCERNING 

preceded the present state of vice and misery, I hear 
them with attention and with reverence. But when 
philosophers, who pretend to neglect authority, and 
to cultivate reason, hold the same discourse, I pay 
them not, I own, the same obsequious submission and 
pious deference. I ask, who carried them into the 
celestial regions, who admitted them into the coun- 
cils of the gods, who opened to them the book of fate, 
that they thus rashly affirm, that their deities have 
executed, or will execute, any purpose beyond what 
has actually appeared ? If they tell me, that they have 
mounted on the steps or by the gradual ascent of 
reason, and by drawing inferences from effects to 
causes, I still insist, that they have aided the ascent 
of reason by the wings of imagination; otherwise they 
could not thus change their manner of inference* and 
argue from causes to effects ; presuming, that a more 
perfect production than the present world would be 
more suitable to such perfect beings as the gods, and 
forgetting that they have no reason to ascribe to these 
celestial beings any perfection or any attribute, but 
what can be found in the present world. 

Hence all the fruitless industry to account for the 
ill appearances of nature, and save the honour of the 
gods j while we must acknowledge the reality of that 
evil and disorder, with which the world so much 
abounds. The obstinate and intractable qualities of 
matter, we are told, or the observance of general laws, 
or some such reason, is the sole cause, which controlled 
the power and benevolence of Jupiter, and obliged 
him to create mankind and every sensible creature so 
imperfect and so unhappy. These attributes then, 
are, it seems, beforehand, taken for granted, in their 
greatest latitude. And upon that supposition, I own 



HUMAN UNDERSTANDING. 147 

that such conjectures may, perhaps, be admitted as 
plausible solutions of the ill phenomena. But still I 
ask, Why take these attributes for granted, or why 
ascribe to the cause any qualities but what actually 
appear in the effect ? Why torture your brain to jus- 
tify the course of nature upon suppositions, which, for 
aught you know, may be entirely imaginary, and of 
which there are to be found no traces in the course of 
nature ? 

The religious hypothesis, therefore, must be con- 
sidered only as a particular method of accounting for 
the visible phenomena of the universe : but no just 
reasoner will ever presume to infer from it any single 
fact, and alter or add to the phenomena, in any single 
particular. If you think, that the appearances of 
things prove such causes, it is allowable for you to 
draw an inference concerning the existence of these 
causes. In such complicated and sublime subjects, 
every one should be indulged in the liberty of conjec- 
ture and argument. But here you ought to rest. If 
you come backward, and arguing from your inferred 
causes, conclude, that any other fact has existed, or 
will exist, in the course of nature, which may serve as 
a fuller display of particular attributes ; I must ad- 
monish you, that you have departed from the method 
of reasoning, attached to the present subject, and 
have certainly added something to the attributes of 
the cause, beyond what appears in the effect ; other- 
wise you could never, with tolerable sense or pro- 
priety, add anything to the effect, in order to render 
it more worthy of the cause. 

Where, then, is the odiousness of that doctine, 
which I teach in my school, or rather, whicn I exam- 
ine in my gardens ? Or what do you find in this 



1 48 AN ENQ UIR Y CONCERNING 

whole question, wherein the security of good morals, 
or the peace and order of society, is in the least con- 
cerned ? 

I deny a providence, you say, and supreme gov- 
ernor of the world, who guides the course of events, 
and punishes the vicious with infamy and disappoint- 
ment, and rewards the virtuous with honour and suc- 
cess, in all their undertakings. But surely, I deny 
not the course itself of events, which lies open to 
every one's inquiry and examination. I acknowledge, 
that, in the present order of things, virtue is attended 
with more peace of mind than vice, and meets with a 
more favourable reception from the world. I am sen- 
sible, that, according to the past experience of man- 
kind, friendship is the chief joy of human life, and 
moderation the only source of tranquillity and happi- 
ness. I never balance between the virtuous and the 
vicious course of life; but am sensible, that, to a well- 
disposed mind, every advantage is on the side of the 
former. And what can you say more, allowing all 
your suppositions and reasonings ? You tell me, 
indeed, that this disposition of things proceeds from 
intelligence and design. But whatever it proceeds 
from, the disposition itself, on which depends our 
happiness or misery, and consequently our conduct 
and deportment in life is still the same. It is still 
open for me, as well as you, to regulate my behaviour, 
by my experience of past events. And if you affirm, 
that, while a divine providence is allowed, and a su- 
preme distributive justice in the universe, I ought to 
expect some more particular reward of the good, and 
punishment of the bad, beyond the ordinary course of 
events ; I here find the same fallacy, which I have 
before endeavoured to detect. You persist in imagin- 



HUMAN UNDERSTANDING. 149 

ing, that, if we grant that divine existence, for which 
you so earnestly contend, you may safely infer conse- 
quences from it, and add something to the experienced 
order of nature, by arguing from the attributes which 
you ascribe to your gods. You seem not to remember, 
that all your reasonings on this subject can only be 
drawn from effects to causes; and that every argu- 
ment, deducted from causes to effects, must of neces- 
sity be a gross sophism; since it is impossible for you 
to know anything of the cause, but what you have 
antecedently, not inferred, but discovered to the full, 
in the effect. 

But what must a philosopher think of those vain 
reasoners, who, instead of regarding the present scene 
of things as the sole object of their contemplation, so 
far reverse the whole course of nature, as to render 
this life merely a passage to something farther; a 
porch, which leads to a greater, and vastly different 
building ; a prologue, which serves only to introduce 
the piece, and give it more grace and propriety? 
Whence, do you think, can such philosophers derive 
their idea of the gods? From their own conceit and 
imagination surely. For if they derived it from the 
present phenomena, it would never point to anything 
farther, but must be exactly adjusted to them. That 
the divinity may possibly be endowed with attributes, 
which we have never seen exerted ; may be governed 
by principles of action, which we cannot discover to 
be satisfied : all this will freely be allowed. But still 
this is mere possibility and hypothesis. We never can 
have reason to infer any attributes, or any principles 
of action in him, but so far as we know them to have 
been exerted and satisfied. 

4 re there any marks of a distributive justice in the 



i 5 o AN ENQUIRY CONCERNING 

world ? If you answer in the affirmative, I conclude, 
that, since justice here exerts itself, it is satisfied. If 
you reply in the negative, I conclude, that you have 
then no reason to ascribe justice, in our sense of it, 
to the gods. If you hold a medium between affirma- 
tion and negation, by saying, that the justice of the 
gods, at present, exerts itself in part, but not in its full 
extent; I answer, that you have no reason to give it 
any particular extent, but only so far as you see it, at 
present, exert itself. 

Thus I bring the dispute, O Athenians, to a short 
issue with my antagonists. The course of nature lies 
open to my contemplation as well as to theirs. The 
experienced train of events is the great standard, by 
which we all regulate our conduct. Nothing else can 
be appealed to in the field, or in the senate. Nothing 
else ought ever to be heard of in the school, or in the 
closet. In vain would our limited understanding break 
through those boundaries, which are too narrow for 
our fond imagination. While we argue from the course 
of nature, and infer a particular intelligent cause, 
which first bestowed, and still preserves order in the 
universe, we embrace a principle, which is both un- 
certain and useless. It is uncertain; because the sub- 
ject lies entirely beyond the reach of human experi- 
ence. It is useless ; because our knowledge of this 
cause being derived entirely from the course of nature, 
we can never, according to the rules of just reasoning, 
return back from the cause with any new inference, 
or making additions to the common and experienced 
course of nature, establish any new principles of con- 
duct and behaviour. 



HUMAN 1 UNDERSTANDING. 151 

I observe (said I, finding he had finished his ha 
rangue) that you neglect not the artifice of the dema- 
gogues of old ; and as you were pleased to make me 
stand for the people, you insinuate yourself into my 
favour by embracing those principles, to which, you 
know, I have always expressed a particular attach- 
ment. But allowing you to make experience (as in- 
deed I think you ought) the only standard of our 
judgement concerning this, and all other questions of 
fact ; I doubt not but, from the very same experience, 
to which you appeal, it may be possible to refute this 
reasoning, which you have put into the mouth of Epi- 
curus. If 3 7 ou saw, for instance, a half-finished build- 
ing, surrounded with heaps of brick and stone and 
mortar, and all the instruments of masonry; could you 
not infer from the effect, that it was a work of design 
and contrivance ? And could you not return again, 
from this inferred cause, to infer new additions to the 
effect, and conclude, that the building would soon be 
finished, and receive all the further improvements, 
which art could bestow upon it ? If you saw upon 
the sea-shore the print of one human foot, you would 
conclude, that a man had passed that way, and that 
he had also left the traces of the other foot, though 
effaced by the rolling of the sands or inundation of the 
waters. Why then do you refuse to admit the same 
method of reasoning with regard to the order of na- 
ture? Consider the world and the present life only as 
an imperfect building, from which you can infer a su- 
perior intelligence; and arguing from that superior 
intelligence, which can leave nothing imperfect ; why 
may you not infer a more finished scheme or plan, 
which will receive its completion in some distant point 
of space or time? Are not these methods of reasoning 



1 52 AN ENQ UIR Y CONCERNING 

exactly similar? And under what pretence can you 
embrace the one, while you reject the other? 

The infinite difference of the subjects, replied he, 
is a sufficient foundation for this difference in my con- 
clusions. In works of human art and contrivance, it is 
allowable to advance from the effect to the cause, and 
returning back from the cause, to form new inferences 
concerning the effect, and examine the alterations, 
which it has probably undergone, or may still undergo. 
But what is the foundation of this method of reasoning? 
Plainly this : that man is a being, whom we know by 
experience, whose motives and designs we are ac- 
quainted with, and whose projects and inclinations 
have a certain connexion and coherence, according to 
the laws which nature has established for the govern- 
ment of such a creature. When, therefore, we find, 
that any work has proceeded from the skill and indus 
try of man ; as we are otherwise acquainted with the 
nature of the animal, we can draw a hundred infer- 
ences concerning what may be expected from him : 
and these inferences will all be founded in experience 
and observation. But did we know man only from 
the single work or production which we examine, it 
were impossible for us to argue in this manner; be- 
cause our knowledge of all the qualities, which we 
ascribe to him, being in that case derived from the 
production, it is impossible they could point to any- 
thing further, or be the foundation of any new infer- 
ence. The print of a foot in the sand can only prove, 
when considered alone, that there was some figure 
adapted to it, by which it was produced: but the print 
of a human foot proves likewise, from our other expe- 
rience, that there was probably another foot, which 
also left its impression, though effaced by time or 



HUMAN UNDERSTANDING 153 

other accidents. Here we mount from the effect to 
the cause; and descending again from the cause, infer 
alterations in the effect; but this is not a continuation 
of the same simple chain of reasoning. We compre- 
hend in this case a hundred other experiences and 
observations, concerning the usual figure and members 
of that species of animal, without which this method 
of argument must be considered as fallacious and 
sophistical. 

The case is not the same with our reasonings from 
the works of nature. The Deity is known to us only 
by his productions, and is a single being in the uni- 
verse, not comprehended under any species or genus, 
from whose experienced attributes or qualities, we can, 
by analogy, infer any attribute or quality in him. As 
the universe shews wisdom and goodness, we infer 
wisdom and goodness. As it shews a particular de- 
gree of these perfections, we infer a particular degree 
of them, precisely adapted to the effect which we ex- 
amine. But further attributes or further degrees of 
the same attributes, we can never be authorised to 
infer or suppose, by any rules of just reasoning. Now, 
without some such license of supposition, it is impos- 
sible for us to argue from the cause, or infer any alter- 
ation in the effect, beyond what has immediately fallen 
under our observation. Greater good produced by 
this Being must still prove a greater degree of good- 
ness : a more impartial distribution of rewards and 
punishments must proceed from, a greater regard to 
justice and equity. Every supposed addition to the 
works of nature makes an addition to the attributes of 
the Author of nature ; and consequently, being en- 
tirely unsupported by any reason or argument, can 



154 AN £NQ UIR Y CONCERNING 

never be admitted but as mere conjecture and hy- 
pothesis. 1 

The great source of our mistake in this subject, 
and of the unbounded licence of conjecture, which we 
indulge, is, that we tacitly consider ourselves, as in 
the place of the Supreme Being, and conclude, that 
he will, on every occasion, observe the same conduct, 
which we ourselves, in his situation, would have em- 
braced as reasonable and eligible. But, besides that 
the ordinary course of nature may convince us, that 
almost everything is regulated by principles and max- 
ims very different from ours ; besides this, I say, it 
must evidently appear contrary to all rules of analogy 
to reason, from the intentions and project of men, tos 
those of a Being so different, and so much superior. 
In, human nature, there is a certain experienced co- 
herence of designs and inclinations; so that when, 
from any fact, we have discovered one intention of 
any man, it may often be reasonable, from experience, 
to infer another, and draw a long chain of conclusions 
concerning his past or future conduct. But this 

1 In general, it may, I think, be established as a maxim, that where any 
cause is known only by its particular effects, it must be impossible to infer 
any new effects from that cause; since the qualities, which are requisite to 
produce these new effects along with the former, must either be different, or 
superior, or of more extensive operation, than those which simply produced 
the effect, whence alone the cause is supposed to be known to us. We can 
never, therefore, have any reason to suppose the existence of these qualities. 
To say, that the new effects proceed only from a continuation of the same 
energy, which is already known from the first effects, will not remove the 
difficulty. For even granting this to be the case (which can seldom be sup- 
posed), the very continuation and exertion of a like energy (for it is impos- 
sible it can be absolutely the same), I say, this exertion of a like energy, in a 
different period of space and time, is a very arbitrary supposition, and what 
there cannot possibly be any traces cf in the effects, frGin which a 1 .! our 
knowledge of the cause is originally derived. Let the inferred cause be 
exactly proportioned (as it should be) to the known effect; and it is impos- 
sible that it can possess any qualities, from which new or different effects can 
be inferred. 






HUMAN UNDERSTANDING. 155 

method of reasoning can never have place with regard 
to a Being, so remote and incomprehensible, who 
bears much less analogy to any other being in the uni- 
verse than the sun to a waxen taper, and who dis- 
covers himself only by some faint traces or outlines, 
beyond which we have no authority to ascribe to him 
any attribute or perfection. What we imagine to be 
a superior perfection, may really be a defect. Or were 
it ever so much a perfection, the ascribing of it to the 
Supreme Being, where it appears not to have been 
really exerted, to the full, in his works, savours more 
of flattery and panegyric, than of just reasoning and 
sound philosophy. All the philosophy, therefore, in 
the world, and all the religion, which is nothing but a 
species of philosophy, will never be able to carry us 
beyond the usaal course of experience, or give us 
measures of conduct and behaviour different from 
those which are furnished by reflections on common 
life. No new fact can ever be inferred from the reli- 
gious hypothesis ; no event foreseen or foretold; no 
reward or punishment expected or dreaded, beyond 
what is already known by practice and observation. 
So that my apology for Epicurus will still appear 
solid and satisfactory; nor have the political interests 
of society any connexion with the philosophical dis- 
putes concerning metaphysics and religion. 

There is still one circumstance, replied I, which 
you seem to have overlooked. Though I should allow 
your premises, I must deny your conclusion. You 
conclude, that religious doctrines and reasonings can 
have no influence on life, because the}' ought to have 
no influence ; never considering, that men reason not 
in the same manner you do, but draw many conse- 
quences from the belief of a divine Existence, and sup- 



i 5 6 AN ENQUIRY CONCERNING 

pose that the Deity will inflict punishments on vice, 
and bestow rewards on virtue, beyond what appear in 
the ordinary course of nature. "Whether this reason- 
ing of theirs be just or not, is no matter. Its influence 
on their life and conduct must still be the same. And, 
those, who attempt to disabuse them of such preju- 
dices, may, for aught I know, be good reasoners, but I 
cannot allow them to be good citizens and politicians; 
since they free men from one restraint upon their pas- 
sions, and make the infringement of the laws of soci- 
ety, in one respect, more easy and secure. 

After all, I may, perhaps, agree to your general 
conclusion in favour of liberty, though upon different 
premises from those, on which you endeavour to found 
it. I think, that the state ought to tolerate every 
principle of philosophy; nor is there an instance, that 
any government has suffered in its political interests 
by such indulgence. There is no enthusiasm among 
philosophers ; their doctrines are not very alluring to 
the people ; and no restraint can be put upon their 
reasonings, but what must be of dangerous conse- 
quence to the sciences, and even to the state, by pav- 
ing the way for persecution and oppression in points, 
where the generality of mankind are more deeply in- 
terested and concerned. 

But there occurs to me (continued I) with regard 
to your main topic, a difficulty, which I shall just pro- 
pose to you without insisting on it ; lest it lead into 
reasonings of too nice and delicate a nature. In a 
word, I much doubt whether it be possible for a cause 
to be known only by its effect (as you have all along 
supposed) or to be of so singular and particular a na- 
ture as to have no parallel and no similarity with any 
Other cause or object, that has ever fallen under our 



HUMAN UNDERSTANDING 157 

observation. It is only when two species of objects are 
found to be constantly conjoined, that we can infer 
the one from the other; and were an effect presented, 
which was entirely singular, and could not be compre- 
hended under any known species, I do not see, that we 
could form any conjecture or inference at all concern- 
ing its cause. If experience and observation and 
analogy be, indeed, the only guides which we can rea- 
sonably follow in inferences of this nature ; both the 
effect and cause must bear a similarity and resemblance 
to other effects and causes, which we know, and which 
we have found, in many instances, to be conjoined 
with each other. I leave it to your own reflection to 
pursue the consequences of this principle. I shall just 
observe, that, as the antagonists of Epicurus always 
suppose the universe, an effect quite singular and un- 
paralleled, to be the proof of a Deity, a cause no less 
singular and unparalleled ; your reasonings, upon that 
supposition, seem, at least, to merit our attention. 
There is, I own, some difficulty, how we can ever re- 
turn from the cause to the effect, and, reasoning from 
our ideas of the former, infer any alteration on the 
latter, or any addition to it. 



SECTION XII. 

OF THE ACADEMICAL OR SCEPTICAL PHILOSOPHY 

Part I. 

THERE is not a greater number of philosophical 
reasonings, displayed upon any subject, than 
those, v/hich prove the existence of a Deity, and refute 
the fallacies of Atheists; and yet the most religious 
philosophers still dispute whether any man can be so 
blinded as to be a speculative atheist. How shall we 
reconcile these contraditions? The knights-errant, 
who wandered about to clear the world of dragons and 
giants, never entertained the least doubt with regard 
to the existence of these monsters. 

The Sceptic is another enemy of religion, who nat- 
urally provokes the indignation of all divines and 
graver philosophers ; though it is certain, that no man 
ever met with any such absurd creature, or conversed 
with a man, who had no opinion or principle concern- 
ing any subject, either of action or speculation. This 
begets a very natural question ; What is meant by a 
sceptic? And how far is it possible to push these phil- 
osophical principles of doubt and uncertainty? 

There is a species of scepticism, antecedent to all 
study and philosophy, which is much inculcated by 
Des Cartes and others, as a sovereign preservative 
against error and precipitate judgement. It recom- 
mends an universal doubt, not only of all our former 



HUMAN UNDERSTANDING. 159 

opinions and principles, but also of our very faculties; 
of whose veracity, say they, we must assure ourselves, 
by a chain of reasoning, deduced from some original 
principle, which cannot possibly be fallacious or de- 
ceitful. But neither is there any such original prin- 
ciple, which has a prerogative above others, that are 
self-evident and convincing : or if there were, could 
we advance a step beyond it, but by the use of those 
very faculties, of which we are supposed to be already 
diffident. The Cartesian doubt, therefore, were it ever 
possible to be attained by any human creature (as it 
plainly is not) would be entirely incurable; and no 
reasoning could ever bring us to a state of assurance 
and conviction upon any subject. 

It must, however, be confessed, that this species 
of scepticism, when more moderate, may be understood 
in a very reasonable sense, and is a necessary prepar- 
ative to the study of philosophy, by preserving a proper 
impartiality in our judgements, and weaning our mind 
from all those prejudices, which we may have imbibed 
from education or rash opinion. To begin with clear 
and self-evident principles, to advance by timorous 
and sure steps, to review frequently our conclusions, 
and examine accurately all their consequences; though 
by these means we shall make both a slow and a short 
progress in our systems ; are the only methods, by 
which we can ever hope to reach truth, and attain a 
proper stability and certainty in our determinations. 

There is another species of scepticism, consequent 
to science and enquiry, when men are supposed to 
have discovered either the absolute fallaciousness of 
their mental faculties, or their unfitness to reach any 
fixed determination in all those curious subjects of 
speculation, about which they are commonly em- 



i6o 



AN ENQUIRY CONCERNING 



ployed. Even our very senses are brought into dis- 
pute, by a certain species of philosophers; and the 
maxims of common life are subjected to the same 
doubt as the most profound principles or conclusions 
of metaphysics and theology. As these paradoxical 
tenets (if they may be called tenets) are to be met with 
in some philosophers, and the refutation of them in 
several, they naturally excite our curiosity, and make 
us enquire into the arguments, on which they may be 
founded. 

I need not insist upon the more trite topics, em- 
ployed by the sceptics in all ages, against the evidence 
of sense-, such as those which are derived from the im- 
perfection and fallaciousness of our organs, on num- 
berless occasions ; the crooked appearance of an oar 
in water; the various aspects of objects, according to 
their different distances ; the double images which 
arise from the pressing one eye; with many other 
appearances of a like nature. These sceptical topics, 
indeed, are only sufficient to prove, that the senses 
alone are not implicitly to be depended on ; but that 
we must correct their evidence by reason, and by con- 
siderations, derived from the nature of the medium, 
the distance of the object, and the disposition of the 
organ, in order to render them, within their sphere, 
the proper criteria of truth and falsehood. There are 
other more profound arguments against the senses, 
„- which admit not of so easy a solution. 

It seems evident, that men are carried, by a natural 
instinct or prepossession, to repose faith in their 
senses ; and that, without any reasoning, or even al- 
most before the use of reason, we always suppose an 
external universe, which depends not on our percep- 
tion, but would exist, though we and every sensible 



■\ 



HUMAN UNDERSTANDING. 161 

creature were absent or annihilated. Even the animal 
creation are governed by a like opinion, and preserve 
this belief of external objects, in all their thoughts, 
designs, and actions. 

It seems also evident, that, when men follow this 
blind and powerful instinct of nature, they always 
suppose the very images, presented by the senses, to 
be the external objects, and never entertain any sus- 
picion, that the one are nothing but representations of 
the other. This very table, which we see white, and 
which we feel hard, is believed to exist, independent 
of our perception, and to be something external to our 
mind, which perceives it. Our presence bestows not 
being on it : our absence does not annihilate it. It 
preserves its existence uniform and entire, independ- 
ent of the situation of intelligent beings, who perceive 
or contemplate it. 

But this universal and primary opinion of all men 
is soon destroyed by the slightest philosophy, which 
teaches us, that nothing can ever be present to the 
mind but an image or perception, and that the senses 
are only the inlets, through which these images are 
conveyed, without being able to produce any immedi- 
ate intercourse between the mind and the object. The 
table, which we see, seems to diminish, as we remove 
farther from it : but the real table, which exists inde- 
pendent of us, suffers no alteration : it was, therefore, 
nothing but its image, which was present to the mind. 
These are the obvious dictates of reason; and no man, 
who reflects, ever doubted, that the existences, which 
we consider, when we say, this house and that tree, are 
nothing but perceptions in the mind, and fleeting 
copies or representations of other existences, which 
remain uniform and independent. 



1 62 AN ENQUIRY CONCERNING 

So far, then, are we necessitated by reasoning to 
contradict or depart from the primary instincts of na- 
ture, and to embrace a new system with regard to the 
evidence of our senses. But here philosophy finds 
herself extremely embarrassed, when she would justify 
this new system, and obviate the cavils and objections 
of the sceptics. She can no longer plead the infallible 
and irresistible instinct of nature : for that led us to a 
quite different system, which is acknowledged fallible 
and even erroneous. And to justify this pretended 
philosophical system, by a chain of clear and convin- 
cing argument, or even any appearance of argument, 
exceeds the power of all human capacity. 

By what argument can it be proved, that the percep. 
tions of the mind must be caused by external objects, 
entirely different from them, though resembling them 
(if that be possible) and could not arise either from 
the energy of the mind itself, or from the suggestion 
of some invisible and unknown spirit, or from some 
other cause still more unknown to us? It is acknowl- 
edged, that, in fact, many of these perceptions arise 
not from anything external, as in dreams, madness, 
and other diseases. And nothing can be more expli- 
cable than the manner, in which body should so op- 
erate upon mind as ever to convey an image of itself 
to a substance, supposed of so different, and even 
contrary a nature. 

It is a question of fact, whether the perceptions of 
the senses be produced by external objects, resem- 
bling them : how shall this question be determined ? 
By experience surely ; as all other questions of a like 
nature. But here experience is, and must be entirely 
silent, (jhe mind has never anything present to it but 
the perceptions, and cannot possibly reach any expe- 



HUMAN UNDERSTANDING. 163 

rience of their connexion with objects. The supposi- 
tion of such a connexion is, therefore, without any 
foundation in reasoning.) 

vTo have recourse to the veracity of the supreme 
Being, in order to prove the veracity of our senses, is 
surely making a very unexpected circuit. If his vera- 
city were at all concerned in this matter, our senses 
would be entirely infallible; because it is not possible 
that he can ever deceive,) Not to mention, that, if the 
external world be once called in question, we shall be 
at a loss to find arguments, by which we may prove 
the existence of that Being or any of his attributes. 

This is a topic, therefore, in which the profounder 
and more philosophical sceptics will always triumph, 
when they endeavour to introduce an universal doubt 
into all subjects of human knowledge and enquiry. 
Do you follow the instincts and propensities of nature, 
may they say, in assenting to the veracity of sense ? 
But these lead you to believe that the very perception 
or sensible image is the external object. Do you dis- 
claim this principle, in order to embrace a more ra- 
tional opinion, that the perceptions are only represen 
tations of something external? You here depart from 
your natural propensities and more obvious sentiments; 
and yet are not able to satisfy your reason, which can 
never find any convincing argument from experience 
to prove, that the perceptions are connected with any 
external objects. 

There is another sceptical topic of a like nature, 
derived from the most profound philosophy; which 
might merit our attention, were it requisite to dive so 
deep, in order to discover arguments and reasonings, 
which can so little serve to any serious purpose. It 
is universally allowed by modern enquirers, that ali 



1 64 AN ENQ UIR Y CONCERNING 

the sensible qualities of objects, such as hard, soft, hot, 
cold, white, black, &c. are merely secondary, and exist 
not in the objects themselves, but are perceptions of 
the mind, without any external archetype or model, 
which they represent. If this be allowed, with regard 
to secondary qualities, it must also follow, with regard 
to the supposed primary qualities of extension and 
solidity; nor can the latter be any more entitled to 
that denomination than the former. The idea of ex- 
tension is entirely acquired from the senses of sight 
and feeling ; and if all the qualities, perceived by the 
senses, be in the mind, not in the object, the same 
conclusion must reach the idea of extension, which is 
wholly dependent on the sensible ideas or the ideas 
of secondary qualities. Nothing can save us from this 
conclusion, but the asserting, that the ideas of those 
primary qualities are attained by Abstraction, an opin- 
ion, which, if we examine it accurately, we shall find 
to be unintelligible, and even absurd. An extension, 
that is neither tangible nor visible, cannot possibly be 
conceived : and a tangible or visible extension, which 
is neither hard nor soft, black or white, is equally be- 
yond the reach of human conception. Let any man 
try to conceive a triangle in general, which is neither 
Isosceles nor Scalenum, nor has any particular length 
or proportion of sides ; and he will soon perceive the 
absurdity of all the scholastic notions with regard to 
abstraction and general ideas. 1 

1 This argument is drawn from Dr. Berkeley; and indeed most of the 
writings of that very ingenious author form the best lessons of scepticism, 
which are to be found either among the ancient or modern philosophers. 
Bayle not excepted. He professes, however, in his title-page (and undoubt- 
edly with great truth) to have composed his book against the sceptics as well 
as against the atheists and free-thinkers. But that all his arguments, though 
otherwise intended, are, in reality, merely sceptical, appecrs from this, that 
they admit of no answer and produce no conviction. Their only effect is to 



HUMAN UNDERSTANDING. 165 

Thus the first philosophical objection to the evi- j 
dence of sense or to the opinion of external existence 
consists in this, that such an opinion, if rested on nat- 
ural instinct, is contrary to reason, and if referred to 
reason, is contrary to natural instinct, and at the same 
time carries no rational evidence with it, to convince 
an impartial enquirer. The second objection goes 
farther, and represents this opinion as contrary to 
reason : at least, if it be a principle of reason, that all 
sensible qualities are in the mind, not in the object. 
Bereave matter of all its intelligible qualities, both 
primary and secondary, you in a manner annihilate 
it, and leave only a certain unknown, inexplicable 
something, as the cause of our perceptions ; a notion 
so imperfect, that no sceptic will think it worth while 
to contend against it. 

Part II. 

It may seem a very extravagant attempt of the 
sceptics to destroy reason by argument and ratiocina- 
tion ; yet is this the grand scope of all their enquiries 
and disputes. They endeavour to find objections, 
both to our abstract reasonings, and to those which 
regard matter of fact and existence. 

The chief objection against all abstract reasonings 
is derived from the ideas of space and time ; ideas, 
which, in common life and to a careless view, are very 
clear and intelligible, but when they pass through the 
scrutiny of the profound sciences (and they are the 
chief object of these sciences) afford principles, which 
seem full of absurdity and contradiction. No priestly 

cause that momentary amazement and irresolution and confusion, which is 
the result of scepticism. 



166 AN ENQUIRY CONCERNING 

dogmas, invented on purpose to tame and subdue the 
rebellious reason of mankind, ever shocked common 
sense more than the doctrine of the infinite divisibil- 
ity of extension, with its consequences; as they are 
pompously displayed by all geometricians and meta- 
physicians, with a kind of triumph and exultation. A 
real quantity, infinitely less than any finite quantity, 
containing quantities infinitely less than itself, and so 
on in infinitum ; this is an edifice so bold and prodig- 
ious, that it is too weighty for any pretended demon- 
stration to support, because it shocks the clearest and 
most natural principles of human reason. 1 But what 
renders the matter more extraordinary, is, that these 
seemingly absurd opinions are supported by a chain 
of reasoning, the clearest and most natural; nor is it 
possible for us' to allow the premises without admit- 
ting the consequences. Nothing can be more convin- 
cing and satisfactory than all the conclusions concern- 
ing the properties of circles and triangles ; and yet> 
when these are once received, how can we deny, that 
the angle of contact between a circle and its tangent 
is infinitely less than any rectilineal angle, that as you 
may increase the diameter of the circle in infinitum, 
this angle of contact becomes still less, even in infini- 
tum, and that the angle of contact between other curves 
and their tangents may be infinitely less than those 
between any circle and its tangent, and so on, in infi- 

1 Whatever disputes there may be about mathematical points, we must 
allow that there are physical points; that is, parts of extension, which cannot 
be divided or lessened, either by the eye or imagination. These images, 
then, which are present to the fancy or senses, are absolutely indivisible, and 
consequently must be allowed by mathematicians to be infinitely less than 
any real part of extension; and yet nothing appears more certain to reason, 
than that an infinite number of them composes an infinite extension. How 
much more an infinite number of those infinitely small parts of extension, 
which are still supposed infinitely divisible. 



HUMAN UNDERSTANDING, 167 

nitum ? The demonstration of these principles seems 
as unexceptionable as that which proves the three 
angles of a triangle to be equal to two right ones, 
though the latter opinion be natural and easy, and the 
former big with contradiction and absurdity. Reason 
here seems to be thrown into a kind of amazement and 
suspence, which, without the suggestions of any scep- 
tic, gives her a diffidence of herself, and of the ground 
on which she treads. She sees a full light, which illu- 
minates certain places ; but that light borders upon 
the most profound darkness. And between these she 
js so dazzled and confounded, that she scarcely can 
pronounce with certainty and assurance concerning 
any one object. 

The absurdity of these bold determinations of the 
abstract sciences seems to become, if possible, still 
more palpable with regard to time than extension. 
An infinite number of real parts of time, passing in 
succession, and exhausted one after another, appears 
so evident a contradiction, that no man, one should 
think, whose judgement is not corrupted, instead of 
being improved, by the sciences, would ever be able 
to admit of it. 

Yet still reason must remain restless, and unquiet, 
even with regard to that scepticism, to which she is 
driven by these seeming absurdities and contradic- 
tions. How any clear, distinct idea can contain cir- 
cumstances, contradictory to itself, or to any other 
clear, distinct idea, is absolutely incomprehensible; 
and is, perhaps, as absurd as any proposition, which 
can be formed. So that nothing can be more scep- 
tical, or more full of doubt and hesitation, than this 
scepticism itself, which arises *rom some of the par- 



168 AN ENQUIRY CONCERNING 

adoxical conclusions of geometry or the science of 
quantity. 1 

The sceptical objections to moral evidence, or to 
the reasonings concerning matter of fact, are either 
popular or philosophical. The popular objections are 
derived from the natural weakness of human under- 
standing; the contradictory opinions, which have been 
entertained in different ages and nations ; the varia- 
tions of our judgement in sickness and health, youth 
and old age, prosperity and adversity ; the perpetual 
contradiction of each particular man's opinions and 
sentiments ; with many other topics of that kind. It 
is needless to insist farther on this head. These objec- 
tions are but weak. For as, in common life, we rea- 
son every moment concerning fact and existence, and 
cannot possibly subsist, without continually employing 
this species of argument, any popular objections, de- 
rived from thence, must be insufficient to destroy that 
evidence. The great subverter of Pyrrhonism or the 
excessive principles of scepticism is action, and em- 
ployment, and the occupations of common life. These 



1 It seems to me not impossible to avoid these absurdities and contradic- 
tions, if it be admitted, that there is no such thing as abstract or general 
ideas, properly speaking; but that all general ideas are, in reality, particular- 
ones, attached to a general term, which recalls, upon occasion, other partic- 
ular ones, that resemble, in certain circumstances, the idea, present to the 
mind. Thus when the term Horse is pronounced, we immediately figure to 
ourselves the idea of a black or a white animal, of a particular size or figure: 
But as that term is also usually applied to animals of other colours, figures 
and sizes, these ideas, though not actually present to the imagination, are 
easily recalled; and our reasoning and conclusion proceed in the same way, 
as if they were actually present. If this be admitted (as seems reasonable) 
it follows that all the ideas of quantity, upon which mathematicians reason, 
are nothing but particular, and such as are suggested by the senses and im- 
agination, and consequently, cannot be infinitely divisible. It is sufficient tu 
have dropped this hint at present, without prosecuting it any farther. It cer 
ta T nly concerns all lovers of science not to expose themselves to the ridicule 
I contempt of the ignorant by their conclusions; and this seems the readi- 
|st solution of these difficulties. 



HUMAN UNDERSTANDING. 169 

principles may flourish and triumph in the schools ; 
where it is, indeed, difficult, if not impossible, to re- 
fute them. But as soon as they leave the shade, and 
by the presence of the real objects, which actuate our 
passions and sentiments, are put in opposition to the 
more powerful principles of our nature, they vanish 
like smoke, and leave the most determined sceptic in 
the same condition as other mortals. 

The sceptic, therefore, had better keep within his 
proper sphere, and display those philosophical objec- 
tions, which arise from more profound researches. 
Here he seems to have ample matter of triumph; 
while he justly insists, that all our evidence for any 
matter of fact, which lies beyond the testimony of 
sense or memory, is derived entirely from the relation 
of cause and effect ; that we have no other idea of this 
relation than that of two objects, which have been 
frequently conjoined together ; that we have no argu- 
ment to convince us, that objects, which have, in our 
experience, been frequently conjoined, will likewise, 
in other instances, be conjoined in the same manner ; 
and that nothing leads us to this inference but custom 
or a certain instinct of our nature ; which it is indeed 
difficult to resist, but which, like other instincts, may 
be fallacious and deceitful. While the sceptic insists 
upon these topics, he shows his force, or rather, in- 
deed, his own and our weakness ; and seems, for the 
time at least, to destroy all assurance and conviction. 
These arguments might be displayed at greater length, 
if any durable good or benefit to society could ever 
be expected to result from them. 

For here is the chief and most confounding objec- 
tion to excessive scepticism, that no durable good can 
ever result from it ; while it remains in its full force 



170 AN ENQUIR Y CONCERNING 

and vigour. We need only ask such a sceptic, What 
his meaning is? And what he proposes by all these curious 
researches ? He is immediately at a loss, and knows 
not what to answer, A Copernican or Ptolemaic, who 
supports each his different system of astronomy, may 
hope to produce a conviction, which will remain con- 
stant and durable, with his audience. A Stoic or 
Epicurean displays principles, which may not be dur- 
able, but which have an effect on conduct and beha- 
viour. But a Pyrrhonian cannot expect, that his phi- 
losophy will have any constant influence on the mind : 
or if it had, that its influence would be beneficial to 
society. On the contrary, he must acknowledge, if he 
will acknowledge anything, that all human life must 
perish, were his principles universally and steadily to 
prevail. All discourse, all action would immediately 
cease; and men remain in a total lethargy, till the 
necessities of nature, unsatisfied, put an end to their 
miserable existence. It is true ; so fatal an event is 
very little to be dreaded. Nature is always too strong 
for principle. And though a Pyrrhonian may throw 
himself or others into a momentary amazement and 
confusion by his profound reasonings; the first and 
most trival event in life will put to flight all his doubts 
and scruples, and leave him the same, in every point 
of action and speculation, with the philosophers of 
every other sect, or with those who never concerned 
themselves in any philosophical researches. When he 
awakes from his dream, he will be the first to join in 
the laugh against himself, and to confess, that all his 
objections are mere amusement, and can have no 
other tendency than to show the whimsical condition 
of mankind, who must act and reason and believe ; 
though they are not able, by their most diligent en- 



HUMAN UNDERSTANDING. 171 

quiry, to satisfy themselves concerning the foundation 
of these operations, or to remove the objections, which 
may be raised against them. 

Part III. 

There is, indeed, a more mitigated scepticism or 
academical philosophy, which may be both durable 
and useful, and which may, in part, be the result of 
this Pyrrhonism, or excessive scepticism, when its un- 
distinguished doubts are, in some measure, corrected 
by common sense and reflection. The greater part of 
mankind are naturally apt to be affirmative and dog- 
matical in their opinions ; and while they see objects 
only on one side, and have no idea of any counterpois- 
ing argument, they throw themselves precipitately 
into the principles, to which they are inclined; nor 
have they any indulgence for those who entertain op- 
posite sentiments. To hesitate or balance perplexes 
their understanding, checks their passion, and sus- 
pends their action. They are, therefore, impatient 
till they escape from a state, which to them is so un- 
easy : and they think, that they could never remove 
themselves far enough from it, by the violence of their 
affirmations and obstinacy of their belief. But could 
such dogmatical reasoners become sensible of the 
strange infirmities of human understanding, even in 
its most perfect state, and when most accurate and 
cautious in its determinations; such a reflection would 
naturally inspire them with more modesty and reserve, 
and diminish their fond opinion of themselves, and 
their prejudice against antagonists. The illiterate 
may reflect on the disposition of the learned, who, 
amidst all the advantages of study and reflection, are 



172 AN ENQ UIR Y CONCERNING 

commonly still diffident in their determinations : and 
if any of the learned be inclined, from their natural 
temper, to haughtiness and obstinacy, a small tincture 
of Pyrrhonism might abate their pride, by showing 
them, that the few advantages, which they may have 
attained over their fellows, are but inconsiderable, if 
compared with the universal perplexity and confusion, 
which is inherent in human nature. In general, there 
is a degree of doubt, and caution, and modesty, which, 
in all kinds of scrutiny and decision, ought for ever 
to accompany a just reasoner. 

Another species of mitigated scepticism which may 
be of advantage to mankind, and which may be the 
natural result of the Pyrrhonian doubts and scruples, 
is the limitation of our enquiries to such subjects as 
are best adapted to the narrow capacity of human 
understanding. The imagination of man is naturally 
sublime, delighted with whatever is remote and extra- 
ordinary, and running, without control, into the most 
distant parts of space and time in order to avoid the 
objects, which custom has rendered too familiar to it. 
r A correct judgement observes a contrary method, and 
avoiding all distant and high enquiries, confines itself 
to common life, and to such subjects as fall under 
daily practice and experience ; leaving the more sub- 
lime topics to the embellishment of poets and orators, 
or to the arts of priests and politicians. ' To bring us 
to so salutary a determination, nothing can be more 
serviceable, than to be once thoroughly convinced of 
the force of the Pyrrhonian doubt, and of the impos- 
sibility, that anything, but the strong power of natural 
instinct, could free us from it. Those who have a 
propensity to philosophy, will still continue their re- 
searches; because they reflect, that, besides the im- 



HUMAN UNDERSTANDING. 173 

mediate pleasure, attending such an occupation, phil- 
osophical decisions are nothing but the reflections of 
common life, methodized and corrected. But they 
will never be tempted to go beyond common life, so 
long as they consider the imperfection of those facul- 
ties which they employ, their narrow reach, and their 
inaccurate operations. While we cannot give a satis- 
factory reason, why we believe, after a thousand expe- 
riments, that a stone will fall, or fire burn; can we 
ever satisfy ourselves concerning any determination, 
which we may form, with regard to the origin of worlds, 
and the situation of nature, from, and to eternity ? S 

This narrow limitation, indeed, of our enquiries, 
is, in every respect, so reasonable, that it suffices to 
make the slightest examination into the natural pow- 
ers of the human mind and to compare them with 
their objects, in order to recommend it to us. We 
shall then find what are the proper subjects of science 
and enquiry. 

It seems to me, that the only objects of the abstract 
science or of demonstration are quantity and number, 
and that all attempts to extend this more perfect spe- 
cies of knowledge beyond these bounds are mere soph- 
istry and illusion. As the component parts of quantity 
and number are entirely similar, their relations become 
intricate and involved; and nothing can be more cu- 
rious, as well as useful, than to trace, by a variety of 
mediums their equality or inequality, through their 
different appearances. But as all other ideas are 
clearly distinct and different from each other, we can 
never advance farther, by our utmost scrutiny, than 
to observe this diversity, and, by an obvious reflection, 
pronounce one thing not to be another. Or if there 
be any difficulty in these decisions, it proceeds entirely 



174 AN ENQUIRY CONCERNING 

from the undeterminate meaning of words, which is 
corrected by juster definitions. That the square of the 
hypothenuse is equal to the squares of the other two sides, 
cannot be known, let the terms be ever so exactly de- 
fined, without a train of reasoning and enquiry. But 
to convince us of this proposition, that where there is 
no property, there can be no injustice, it is only necessary 
to define the terms, and explain injustice to be a vio- 
lation of property. This proposition is, indeed, noth- 
ing but a more imperfect definition. It is the same 
case with all those pretended syllogistical reasonings, 
which may be found in every other branch of learning, 
except the sciences of quantity and number; and these 
may safely, I think, be pronounced the only proper 
objects of knowledge and demonstration. 

All other enquiries of men regard only matter of 
fact and existence ; and these are evidently incapable 
of demonstration. Whatever is may not be. No nega- 
tion of a fact can involve a contradiction. The non- 
existence of any being, without exception, is as clear 
and distinct an idea as its existence. The proposition, 
which affirms it not to be, however false, is no less 
conceivable and intelligible, than that which affirms it 
to be. The case is different with the sciences, properly 
so called. Every proposition, which is not true, is 
there confused and unintelligible. That the cube root 
of 64 is equal to the half of 10, is a false proposition, 
and can never be distinctly conceived. But that Cae- 
sar, or the angel Gabriel, or any being never existed, 
may be a false proposition, but still is perfectly con- 
ceivable, and implies no contradiction. 

The existence, therefore, of any being can only be 
proved by arguments from its cause or its effect ; and 
these arguments are founded entirely on experience. 



HUMAN UNDERSTANDING. 175 

If we reason a priori, anything may appear able to 
produce anything. The falling of a pebble may, for 
aught we know, extinguish the sun ; or the wish of a 
man control the planets in their orbits. It is only ex- 
perience, which teaches us the nature and bounds of 
cause and effect, and enables us to infer the existence 
of one object from that of another. 1 Such is the foun- 
dation of moral reasoning, which forms the greater 
part of human knowledge, and is the source of all 
human action and behaviour. 

Moral reasonings are either concerning particular 01 
general facts. All deliberations in life regard the for- 
mer ; as also all disquisitions in history, chronology, 
geography, and astronomy. 

The sciences, which treat of general facts, are pol- 
itics, natural philosophy, physic, chemistry, &c. where 
the qualities, causes and effects of a whole species of 
objects are enquired into. 

Divinity or Theology, as it proves the existence of 
a Deity, and the immortality of souls, is composed 
partly of reasonings concerning particular, partly con- 
cerning general facts It has a foundation in reason, 
so far as it is supported by experience. But its best 
and most solid foundation is faith and divine reve- 
lation. 

Morals and criticism are not so properly objects of 
the understanding as of taste and sentiment. Beauty, 
whether moral or natural, is felt, more properly than 
perceived. Or if we reason concerning it, and endeav- 
our to fix its standard, we regard a new fact, to wit, 

1 That impious maxim of tha ancient philosophy, Ejt nikilo, nihil fit, by 
which the creation of matter was excluded, ceases to be a maxim according 
to this philosophy. Not only the wi.l of the supreme Being may create mat- 
ter; but, for aught we know a priori, the will of any other being might create 
it, or any other cause, that the most whimsical imagination can assign. 



176 AN ENQ UIR Y CONCERNING 

the general tastes of mankind, or some such fact, 
which may be the object of reasoning and enquiry. 

When we run over libraries, persuaded of these 
principles, what havoc must we make ? If we take in 
our hand any volume; of divinity or school metaphys- 
ics, for instance; let us ask, Does it contain any abstract 
reasoning concerning quantity or number ? No. Does it 
contain any experimental reasoning concerning matter of 
fact and existence ? No. Commit it then to the flames: 
for it can contain nothing but sophistry and illusion. 



SELECTIONS FROM 

A TEE A TISE OE HUMAN NA TUBE 

BOOK I. 
BY DAVID HUME 



TREATISE 

O F 

Human Nature: 

BEING 

An Attempt to introduce the ex- 
perimental Method of Reafoning 

I NTO 

MORAL SUBJECTS. 



Rara temporum felicitas, ubi /entire, quce velis ; & qua 
fen ias } dicere licet. Tacit. 



Book I. 



OF THE 
UNDERSTANDING. 



LONDON: 

Printed for John Noon, at the White-Hart, near 

Mercer's- Chape I'm Cheapfide. 



MDCCXXXIX. 



The Contents of 
A Treatise of Human Nature 



BOOK I. 

Of the Understanding. 
PART I. 
Of ideas; their origin, composition, abstraction connexion, fyc. 
sect. PA 

I. Of the origin of our ideas .... 

II. Division of the subject ..... 

III. Of the ideas of the memory and imagination . . 
xV. Of the connexion or association of ideas 
V. Of relations ....... 

* VI. Of modes and substances .... 

VII. Of abstract ideas ...... 



227 



PART II. 

Of the ideas of space and time. 
I. Of the infinite divisibility of our ideas of space 
and time ........ 

II. Of the infinite divisibility of space and time . 

III. Of the other qualities of our ideas of space and time 

IV. Objections answer'd ...... 

V. The same subject continu'd ..... 

* VI. Of the idea of existence and of external existence . 229 

PART III. 

Of knowledge and probability. 

* I. Of knowledge 185 

* II. Of probability ; and of the idea of cause and effect . 190 

* III. Why a cause is always necessary? . . . .197 

* Only the sections thus indicated are here reproduced. 



l82 



CONTENTS. 



SECT. 

IV. Of the component parts of our reasonings concerning 

causes and effects ..... 
V. Of the impressions of the senses and memory . 
VI. Of the inference from the impression to the idea 
VII. Of the nature of the idea, or belief 

VIII. Of the causes of belief 

IX. Of the effects of other relations, and other habits 
X. Of the influence of belief . . . . 
XI. Of the probability of chances . . . 

XII. Of the probability of causes .... 
XIII. Of unphilosophical probability 
*XI V. Of the idea of necessary connexion 

XV. Rules by which to judge of causes and effects 
XVI. Of the reason of animals .... 



PAGE 



202 



PART IV. 

Of the sceptical and other systems of philosophy 
I. Of scepticism with regard to reason 
II. Of scepticism with regard to the senses 

III. Of the antient philosophy 

IV. Of the modern philosophy 
V. Of the immateriality of the soul 

VI. Of personal identity 
VII. Conclusion of this book 

Appendix . . . . 



€32 

245 
260 



* Only the sections thus indicated are here reproduced. 



THE DOCTRINE OF CAUSALITY 



SELECTIONS FROM 
BOOK I., PART IIL 



BOOK I. 

PART III. 

OF KNOWLEDGE AND PROBABILITY, 

Section I. 

Of knowledge. 

There are 1 seven different kinds of philosophical 
relation, viz. resemblance, identity, relations of time 
and place, proportion in quantity or number, degrees 
in any quality, contrariety, and causation. These re- 
lations may be divided into two classes; into such as 
depend entirely on the ideas, which we compare to- 
gether, and such as may be chang'd without any 
change in the ideas. 'Tis from the idea of a triangle, 
that we discover the relation of equality, which its 
three angles bear to two right ones; and this relation 
is invariable, as long as our idea remains the same. 
On the contrary, the relations of contiguity and dis- 
tance betwixt two objects may be chang'd merely by 
an alteration of their place, without any change on the 
objects themselves or on their ideas; and the place 
depends on a hundred different accidents, which can- 
not be foreseen by the mind. 'Tis the same case with 
identity and causation. Two objects, tho' perfectly re- 
sembling each other, and even appearing in the same 
place at different times, may be numerically different: 
And as the power, by which one object produces an- 
other, is never discoverable merely from their ide^ 
1 Part I., Sect V, 



i86 A TREATISE OF HUMAN NATURE PART III 

'tis evident cause and effect are relations, of which we 
receive information from experience, and not from any 
abstract reasoning or reflexion. There is no single 
phenomenon, even the most simple, which can be 
accounted for from the qualities of the objects, as they 
appear to us; or which we cou'd foresee without the 
help of our memory and experience. 

It appears, therefore, that of these seven philo- 
sophical relations, there remain only four, which de- 
pending solely upon ideas, can be the objects of knowl- 
edge and certainty. These four are resemblance, con- 
trariety, degrees in quality, and proportions in quan- 
tity or number. Three of these relations are discover- 
able at first sight, and fall more properly under the 
province of intuition than demonstration. When any 
objects resemble each other, the resemblance will at 
first strike the eye, or rather the mind; and seldom 
requires a second examination. The case is the same 
with contrariety, and with the degrees of any quality, 
No one can once doubt but existence and non-existence 
destroy each other, and are perfectly incompatible and 
contrary. And tho' it be impossible to judge exactly 
of the degrees of any quality, such as colour, taste, 
heat, cold, when the difference betwixt them is very 
small ; yet 'tis easy to decide, that any of them is supe- 
rior or inferior to another, when their difference is 
considerable. And this decision we always pronounce 
at first sight, without any enquiry or reasoning. 

We might proceed, after the same manner, in fixing 
the proportions of quantity or number, and might at 
one view observe a superiority or inferiority betwixt 
any numbers, or figures; especially where the differ- 
ence is very great and remarkable. As to equality or 
any exact proportion, we can only guess at it from a 



SECT. I BOOK I. OF THE UNDERSTANDING 187 

single consideration ; except in very short numbers, or 
very limited portions of extension; which are com- 
prehended in an instant, and where we perceive an 
impossibility of falling into any considerable error. 
In all other cases we must settle the proportions with 
some liberty, or proceed in a more artificial manner, 

I have already observ'd, that geometry, or the art, 
by which we fix the proportions of figures; tho' it 
much excels, both in universality and exactness, the 
loose judgments of the senses and imagination; yet 
never attains a perfect precision and exactness. Its 
first principles are still drawn from the general appear- 
ance of the objects ; and that appearance can never af- 
ford us any security, when we examine the prodigious 
minuteness of which nature is susceptible. Our ideas 
seem to give a perfect assurance, that no two right 
lines can have a common segment; but if we consider 
these ideas, we shall find, that they always suppose a 
sensible inclination of the two lines, and that where 
the angle they form is extremely small, we have no 
standard of a right line so precise, as to assure us of 
the truth of this proposition. Tis the same case with 
most of the primary decisions of the mathematics. 

There remain, therefore, algebra and arithemetic 
as the only sciences, in which we can carry on a chain 
of reasoning to any degree of intricacy, and yet pre- 
serve a perfect exactness and certainty. We are pos- 
sest of a precise standard, by which we can judge of 
the equality and proportion of numbers ; and according 
as they correspond or not to that standard, we deter- 
mine their relations, without any possibility of error. 
When two numbers are so combin'd, as that the one 
has always an unite answering to every unite of the 
other, we pronounce them equal; and 'tis for want of 



188 A TREATISE OF HUMAN NATURE PART III 

such a standard of equality in extension, that geometry 
can scarce be esteem'd a perfect and infallible science. 

But here it may not be amiss to obviate a difficulty, 
which may arise from my asserting, that tho' geometry 
falls short of that perfect precision and certainty, 
which are peculiar to arithmetic and algebra, yet it 
excels the imperfect judgments of our senses and 
imagination. The reason why I impute any defect 
to geometry, is, because its original and fundamental 
principles are deriv'd merely from appearances; and it 
may perhaps be imagin'd, that this defect must always 
attend it, and keep it from ever reaching a greater 
exactness in the comparison of objects or ideas, than 
what our eye or imagination alone is able to attain. 
I own that this defect so far attends it, as to keep it 
from ever aspiring to a full certainty : But since these 
fundamental principles depend on the easiest and least 
deceitful appearances, they bestow on their conse- 
quences a degree of exactness, of which these conse- 
quences are singly incapable. 'Tis impossible for the 
eye to determine the angles of a chiliagon to be equal 
to 1996 right angles, or to make any conjecture, that 
approaches this proportion; but when it determines, 
that right lines cannot concur; that we cannot draw 
more than one right line between two given points; 
its mistakes can never be of any consequence. And 
this is the nature and use of geometry, to run us up to 
such appearances, as, by reason of their simplicity, 
cannot lead us into any considerable error. 

I shall here take occasion to propose a second 
observation concerning our demonstrative reasonings, 
which is suggested by the same subject of the mathe- 
matics. 'Tis usual with mathematicians, to pretend, 
that those ideas, which are their objects, are of so 



SECT. I BOOK I. OF THE UNDERSTANDING 189 

refin'd and spiritual a nature, that they fall not under 
the conception of the fancy, but must be comprehended 
by a pure and intellectual view, of which the superior 
faculties of the soul are alone capable. The same 
notion runs thro' most parts of philosophy, and is prin- 
cipally made use of to explain our abstract ideas, and 
to shew how we can form an idea of a triangle, for 
instance, which shall neither be an isosceles nor scale- 
num, nor be confin'd to any particular length and 
proportion of sides. Tis easy to see, why philosophers 
are so fond of this notion of some spiritual and refin'd 
perceptions; since by that means they cover many of 
their absurdities, and may refuse to submit to the de- 
cisions of clear ideas, by appealing to such as are 
obscure and uncertain. But to destroy this artifice, we 
need but reflect on that principle so oft insisted on, 
that all our ideas are copy'd from our impressions. 
For from thence we may immediately conclude, that 
since all impressions are clear and precise, the ideas, 
which are copied from them, must be of the same 
nature, and can never, but from our fault, contain any 
thing so dark and intricate. An idea is by its very 
nature weaker and fainter than an impression; but 
being in every other respect the same, cannot imply 
any very great mystery. If its weakness render it 
obscure, 'tis our business to remedy that defect, as 
much as possible, by keeping the idea steady and pre- 
cise ; and till we have done so, 'tis in vain to pretend 
to reasoning and philosophy. 



Section II. 
Of probability ; and of the idea of cause and effect. 

This is all I think necessary to observe concerning 
those four relations, which are the foundation of 
science; but as to the other three, which depend not 
upon the idea, and may be absent or present even while 
that remains the same, 'twill be proper to explain 
them more particularly. These three relations are 
identity, the situations in time and place, and causa- 
tion. 

All kinds of reasoning consist in nothing but a 
comparison, and a discovery of those relations, either 
constant or inconstant, which two or more objects 
bear to each other. This comparison we may make, 
either when both the objects are present to the senses, 
or when neither of them is present, or when only one. 
When both the objects are present to the senses along 
with the relation, we call this perception rather than 
reasoning ; nor is there in this case any exercise of the 
thought, or any action, properly speaking, but a mere 
passive admission of the impressions/thro' the organs 
of sensation. According to this way of thinking, we 
ought not to receive as reasoning any of the observa- 
tions we may make concerning identity, and the rela- 
tions of time and place; since in none of them the mind 
can go beyond what is immediately present to the 
senses, either to discover the real existence or the 
relations of objects. 'Tis only causation, which pro- 
duces such a connexion, as to give us assurance from 



SECT. II BOOK I. OF THE UNDERSTANDING igi 

the existence or action of one object, that 'twas fol- 
low'd or preceded by any other existence or action; 
nor can the other two relations be ever made use of 
in reasoning, except so far as they either affect or are 
affected by it. There is nothing in any objects to per- 
swade us, that they are either always remote or always 
contiguous ; and when from experience and observa- 
tion we discover, that their relation in this particular 
is invariable, we always conclude there is some secret 
cause, which separates or unites them. The same rea- 
soning extends to identity. We readily suppose an 
object may continue individually the same, tho' several 
times absent from and present to the senses ; and 
ascribe to it an identity, notwithstanding the inter- 
ruption of the perception, whenever we conclude, that 
if we had kept our eye or hand constantly upon it, it 
wou'd have convey'd an invariable and uninterrupted 
perception. But this conclusion beyond the impres- 
sions of our senses can be founded only on the con- 
nexion of cause and effect; nor can we otherwise have 
any security, that the object is not chang'd upon us, 
however much the new object may resemble that which 
was formerly present to the senses. Whenever we 
discover such a perfect resemblance, we consider, 
whether it be common in that species of objects; 
whether possibly or probably any cause cou'd operate 
in producing the change and resemblance ; and accord- 
ing as we determine concerning these causes and 
effects, we form our judgment concerning the identity 
of the object. 

Here then it appears, that of those three relations, 
which depend not upon the mere ideas, the only one, 
that can be trac'd beyond our senses, and informs us 
of existences and objects, which we do not see or feel, 



192 A TREATISE OF HUMAN NATURE PART III 

is causation. This relation, therefore, we shall en- 
deavour to explain fully before we leave the subject of 
the understanding. 

To begin regularly, we must consider the idea of 
causation, and see from what origin it is deriv'd. 'Tis 
impossible to reason justly, without understanding per- 
fectly the idea concerning which we reason; and 'tis 
impossible perfectly to understand any idea, without 
tracing it up to its origin, and examining that primary 
impression, from which it arises. The examination of 
the impression bestows a clearness on the idea; and 
the examination of the idea bestows a like clearness 
on all our reasoning. 

Let us therefore cast our eye on any two objects, 
which we call cause and effect, and turn them on all 
sides, in order to find that impression, which produces 
an idea of such prodigious consequence. At first sight 
I perceive, that I must not search for it in any of the 
particular qualities of the objects; since, which-ever of 
these qualities I pitch on, I find some object, that is not 
possest of it, and yet falls under the denomination of 
cause or effect. And indeed there is nothing existent, 
either externally or internally, which is not to be con- 
sider'd either as a cause or an effect; tho' 'tis plain 
there is no one quality, which universally belongs to 
all beings, and gives them a title to that denomination. 

The idea, then, of causation must be deriv'd from 
some relation among objects; and that relation we 
must now endeavour to discover. I find in the first 
place, that whatever objects are consider'd as causes 
or effects, are contiguous; and that nothing can oper- 
ate in a time or place, which is ever so little remov'd 
from those of its existence. Tho' distant objects may 
sometimes seem productive of each other, they are 



SECT. II BOOK I. OF THE UNDERSTANDING 193 

commonly found upon examination to be link'd by a 
chain of causes, which are contiguous among them- 
selves, and to the distant objects; and when in any 
particular instance we cannot discover this connexion, 
we still presume it to exist. We may therefore con- 
sider the relation of contiguity as essential to that 
of causation; at least may suppose it such, according 
to the general opinion, till we can find a more 1 proper 
occasion to clear up this matter, by examining what 
objects are or are not susceptible of juxtaposition and 
conjunction. 

The second relation I shall observe as essential to 
causes and effects, is not so universally acknowledg'd, 
but is liable to some controversy. Tis that of priority 
of time in the cause before the effect. Some pretend 
that 'tis not absolutely necessary a cause shou'd pre- 
cede its effect; but that any object or action, in the 
very first moment of its existence, may exert its pro- 
ductive quality, and give rise to another object or 
action, perfectly co-temporary with itself. But beside 
that experience in most instances seems to contradict 
this opinion, we may establish the relation of priority 
by a kind of inference or reasoning. 'Tis an estab- 
lished maxim both in natural and moral philosophy, 
that an object, which exists for any time in its full 
perfection without producing another, is not its sole 
cause; but is assisted by some other principle, which 
pushes it from its state of inactivity, and makes it 
exert that energy, of which it was secretly possest. 
Now if any cause may be perfectly co-temporary with 
its effect, 'tis certain, according to this maxim, that 
they must all of them be so; since any one of them, 
which retards its operation for a single moment, exerts 

1 Part IV., Sect. V. 



194 A TREATISE OF HUMAN NATURE PART III 

not itself at that very individual time, in which it 
might have operated ; and therefore is no proper cause. 
The consequence of this wou'd be no less than the 
destruction of that succession of causes, which we 
observe in the world; and indeed, the utter annihila- 
tion of time. For if one cause were co-temporary 
with its effect, and this effect with its effect, and so 
on, 'tis plain there wou'd be no such thing as succes- 
sion, and all objects must be co-existent. 

If this argument appear satisfactory, 'tis well. If 
not, I beg the reader to allow me the same liberty, 
which I have us'd in the preceding case, of supposing 
it such. For he shall find, that the affair is of no great 
importance. 

Having thus discover'd or suppos'd the two rela- 
tions of contiguity and succession to be essential to 
causes and effects, I find I am stopt short, and can 
proceed no farther in considering any single instance 
of cause and effect. Motion in one body is regarded 
upon impulse as the cause of motion in another. 
When we consider these objects with the utmost atten- 
tion, we find only that the one body approaches the 
other; and that the motion of it precedes that of the 
other, but without any sensible interval. Tis in vain 
to rack ourselves with farther thought and reflexion 
upon this subject. We can go no farther in consider- 
ing this particular instance. 

Shou'd any one leave this instance, and pretend to 
define a cause, by saying it is something productive of 
another, 'tis evident he wou'd say nothing. For what 
does he mean by production? Can he give any defini- 
tion of it, that will not be the same with tha* of 
causation? If he can; I desire it may be produc'd. If 



SECT. II BOOK I. OF THE UNDERSTANDING 19$ 

he cannot ; he here runs in a circle, and gives a synon- 
imous term instead of a definition. 

Shall we then rest contented with these two rela- 
tions of contiguity and succession, as affording a com- 
pleat idea of causation? By no means. An object 
may be contiguous and prior to another, without being 
consider'd as its cause. There is a necessary con- 
nexion to be taken into consideration; and that rela- 
tion is of much greater importance, than any of the 
other two above-mention'd. 

Here again I turn the object on all sides, in order 
to discover the nature of this necessary connexion, and 
find the impression, or impressions, from which its 
idea may be deriv'd. When I cast my eye on the 
known qualities of objects, I immediately discover that 
the relation of cause and -effect depends not in the 
least on them. When I consider their relations, I can 
find none but those of contiguity and succession ; which 
I have already regarded as imperfect and unsatisfac- 
tory. Shall the despair of success make me assert, 
that I am here possest of an idea, which is not pre- 
ceded by any similar impression? This wou'd be too 
strong a proof of levity and inconstancy ; since the con- 
trary principle has been already so firmly establish'd, 
as to admit of no farther doubt; at least, till we have 
more fully examin'd the present difficulty. 

We must, therefore, proceed like those, who being 
in search of any thing that lies conceal'd from them, 
and not finding it in the place they expected, beat about 
all the neighbouring fields, without any certain view or 
design, in hopes their good fortune will at last guide 
them to what they search for. 'Tis necessary for us 
to leave the direct survey of this question concerning 
the nature of that necessary connexion, which enters 



iq6 A TREATISE OF HUMAN NATURE PART 111 

into our idea of cause and effect ; and endeavour to find 
some other questions, the examination of which will 
perhaps afford a hint, that may serve to clear up the 
present difficulty. Of these questions there occur two, 
which I shall proceed to examine, vis. 

First, For what reason we pronounce it necessary, 
that every thing whose existence has a beginning, 
shou'd also have a cause? 

Secondly, Why we conclude, that such particular 
causes must necessarily have such particular effects; 
and what is the nature of that inference we draw from 
the one to the other, and of the belief we repose in it ? 

I shall only observe before I proceed any farther, 
that tho' the ideas of cause and effect be deriv'd from 
the impressions of reflexion as well as from those of 
sensation, yet for brevity's sake, I commonly mention 
only the latter as the origin of these ideas; tho' I de- 
sire that whatever I say of them may also extend to 
the former. Passions are connected with their objects 
and with one another; no less than external bodies are 
connected together. The same relation, then, of cause 
and effect, which belongs to one, must be common to 
all of them. 



Section III. 
Why a cause is always necessary. 

To begin with the first question concerning the 
necessity of a cause: 'Tis a general maxim in philos- 
ophy, that whatever begins to exist, must have a cause 
of existence. This is commonly taken for granted in 
all reasonings, without any proof given or demanded. 
'Tis suppos'd to be founded on intuition, and to be 
one of those maxims, which tho' they may be deny'd 
with the lips, 'tis impossible for men in their hearts 
really to doubt of. But if we examine this maxim by 
the idea of knowledge above-explain'd, we shall dis- 
cover in it no mark of any such intuitive certainty; 
but on the contrary shall find, that 'tis of a nature 
quite foreign to that species of conviction. 

All certainty arises from the comparison of ideas, 
and from the discovery of such relations as are unal- 
terable, so long as the ideas continue the same. These 
relations are resemblance, proportions in quantity and 
number, degrees of any quality, and contrariety ; none 
of which are imply'd in this proposition, Whatever has 
a beginning has also a cause of existence. That prop- 
osition therefore is not intuitively certain. At least 
any one, who wou'd assert it to be intuitively certain, 
must deny these to be the only infallible relations, and 
must find some other relation of that kind to be im- 
ply'd in it; which it will then be time enough to 
examine. 



198 A TREATISE OP HUMAN NATURE PART 111 

But here is an argument, which proves at once, 
that the foregoing proposition is neither intuitively 
nor demonstrably certain. We can never demonstrate 
the necessity of a cause to every new existence, or new 
modification of existence, without shewing at the same 
time the impossibility there is, that any thing can ever 
begin to exist without some productive principle; and 
where the latter proposition cannot be prov'd, we must 
despair of ever being able to prove the former. Now 
that the latter proposition is utterly incapable of a 
demonstrative proof, we may satisfy ourselves by con- 
sidering, that as all distinct ideas are separable from 
each other, and as the ideas of cause and effect are 
evidently distinct, 'twill be easy for us to conceive any 
object to be non-existent this moment, and existent 
the next, without conjoining to it the distinct idea of 
a cause or productive principle. The separation, there- 
fore, of the idea of a cause from that of a beginning 
of existence, is plainly possible for the imagination ; 
and consequently the actual separation of these objects 
is so far possible, that it implies no contradiction nor 
absurdity; and is therefore incapable of being refuted 
by any reasoning from mere ideas ; without which /tis 
impossible to demonstrate the necessity of a cause. 

Accordingly we shall find upon examination, that 
every demonstration, which has been produc'd for the 
necessity of a cause, is fallacious and sophistical. 
All the points of time and place, 1 say some philoso- 
phers, in which we can suppose any object to begin to 
exist, are in themselves equal ; and unless there be 
some cause, which is peculiar to one time and to one 
place, and which by that means determines and fixes 
the existence, it must remain in eternal suspence; and 

1 Mr. Hobbes. 



SECT. Ill BOOK I. OF THE UNDERSTANDING 199 

the object can never begin to be, for want of some- 
thing to fix its beginning. But I ask ; Is there any more 
difficulty in supposing the time and place to be fix'd 
without a cause, than to suppose the existence to be 
determin'd in that manner? The first question that 
occurs on this subject is always, whether the object 
shall exist or not: The next, when and where it shall 
begin to exist. If the removal of a cause be intuitively 
absurd in the one case, it must be so in the other: 
And if that absurdity be not clear without a proof in 
the one case, it will equally require one in the other. 
The absurdity, then, of the one supposition can never 
be a proof of that of the other; since they are both 
upon the same footing, and must stand or fall by the 
same reasoning. 

The second argument, 2 which I find us'd on this 
head, labours under an equal difficulty. Every thing, 
'tis said, must have a cause ; for if any thing wanted a 
cause, it would produce itself ; that is, exist before it 
existed; which is impossible. But this reasoning is 
plainly unconclusive ; because it supposes, that in our 
denial of a cause we still grant what we expressly 
deny, viz. that there must be a cause ; which therefore 
is taken to be the object itself; and that, no doubt, is 
an evident contradiction. But to say that any thing is 
produc'd, or to express myself more properly, comes 
into existence, without a cause, is not to affirm, that 
'tis itself its own cause; but on the contrary in exclud- 
ing all external causes, excludes a fortiori the thing 
itself which is created. An object, that exists abso- 
lutely without any cause, certainly is not its own cause ; 
and when you assert, that the one follows from the 
other, you suppose the very point in question, and take 

2 Dr. Clarke and others. 



200 A TREATISE OF HUMAN NATURE PART III 

it for granted, that 'tis utterly impossible any thing 
can ever begin to exist without a cause, but that upon 
the exclusion of one productive principle, we must 
still have recourse to another. 

Tis exactly the same case with the 1 third argu- 
ment, which has been employ'd to demonstrate the 
necessity of a cause. Whatever is produc'd without 
any cause, is produc'd by nothing; or in other words, 
has nothing for its cause. But nothing can never be 
a cause, no more than it can be something, or equal 
to two right angles. By the same intuition, that we 
perceive nothing not to be equal to two right angles, 
or not to be something, we perceive, that it can never 
be a cause ; and consequently must perceive, that every 
object has a real cause of its existence. 

I believe it will not be necessary to employ many 
words in shewing the weakness of this argument, after 
what I have said of the foregoing. They are all of 
them founded on the same fallacy, and are deriv'd 
from the same turn of thought. 'Tis sufficient only to 
observe, that when we exclude all causes we really 
do exclude them, and neither suppose nothing nor the 
object itself to be the causes of the existence; and 
consequently can draw no argument from the absurd- 
ity of these suppositions to prove the absurdity of that 
exclusion. If every thing must have a cause, it fol- 
lows, that upon the exclusion of other causes we must 
accept of the object itself or of nothing as causes. 
But 'tis the very point in question, whether every 
thing must have a cause or not ; and therefore, accord- 
ing to all just reasoning, it ought never to be taken 
for granted. 

1 Mr. Locke. 






SECT. Ill BOOK I. OF THE UNDERSTANDING 201 

They are still more frivolous, who say, that every 
effect must have a cause, because 'tis imply'd in the 
very idea of effect. Every effect necessarily pre-sup- 
poses a cause; effect being a relative term, of which 
cause is the correlative. But this does not prove, that 
every being must be preceded by a cause; no more 
than it follows, because every husband must have a 
wife, that therefore every man must be marry'd. The 
true state of the question is, whether every object, 
which begins to exist, must owe its existence to a 
cause; and this I assert neither to be intuitively nor 
demonstratively certain, and hope to have prov'd it 
sufficiently by the foregoing arguments. 

Since it is not from knowledge or any scientific 
reasoning, that we derive the opinion of the necessity 
of a cause to every new production, that opinion must 
necessarily arise from observation and experience. 
The next question, then, shou'd naturally be, how expe- 
rience gives rise to such a principle? But as I find 
it will be more convenient to sink this question in the 
following, Why we conclude, that such particular 
causes must necessarily have such particular effects, 
and why we form an inference from one to another? 
we shall make that the subject of our future enquiry. 
'Twill, perhaps, be found in the end, that the same 
answer will serve for both questions. 

:fc s|s sk sfc sj* ♦ 



Section XIV. 
Of the idea of necessary connexion. 

Having thus explain'd the manner,, in which we 
reason beyond our immediate impressions, and con- 
clude that such particular causes must have such par- 
ticular effects; we must now return upon our foot- 
steps to examine that question, which 1 first occur'd 
to us, and which we dropt in our way, viz. What is 
our idea of necessity, when we say that two objects 
are necessarily connected together. Upon this head 
I repeat what I have often had occasion to observe, 
that as we have no idea, that is not deriv'd from an 
impression, we must find some impression, that gives 
rise to this idea of necessity, if we assert we have really 
such an idea. In order to this I consider, in what 
objects necessity is commonly suppos'd to lie; and 
finding that it is always ascrib'd to causes and effects, 
I turn my eye to two objects suppos'd to be plac'd in 
that relation; and examine them in all the situations, 
of which they are susceptible. I immediately perceive, 
that they are contiguous in time and place, and that 
the object we call cause precedes the other we call 
effect. In no one instance can I go any farther, nor is 
it possible for me to discover any third relation betwixt 
these objects. I therefore enlarge my view to com- 
prehend several instances ; where I find like objects 
always existing in like relations of contiguity and suc- 
cession. At first sight this seems to serve but lit 4 ;*: 

1 Sect. 2. 






SECT. XIV BOOK I. OF THE UNDERSTANDING 203 

to my purpose. The reflection on several instances 
only repeats the same objects; and therefore can never 
give rise to a new idea. But upon farther enquiry I 
find, that the repetition is not in every particular the 
same, but produces a new impression, and by that 
means the idea, which I at present examine. For after 
a frequent repetition, I find, that upon the appear- 
ance of one of the objects, the mind is determined 
by custom to consider its usual attendant, and to con- 
sider it in a stronger light upon account of its rela- 
tion to the first object. 'Tis this impression, then, or 
determination, which affords me the idea of necessity. 
I doubt not but these consequences will at first 
sight be receiv'd without difficulty, as being evident 
deductions from principles, which we have already 
established, and which we have often employ'd in our 
reasonings. This evidence both in the first principles, 
and in the deductions, may seduce us unwarily into the 
conclusion, and make us imagine it contains nothing 
extraordinary, nor worthy of our curiosity. But tho' 
such an inadvertence may facilitate the reception of this 
reasoning, 'twill make it be the more easily forgot; 
for which reason I think it proper to give warning, 
that I have just now examin'd one of the most sublime 
questions in philosophy, vis. that concerning the power 
and efficacy of causes; where all the sciences seem so 
much interested. Such a warning will naturally rouze 
up the attention of the reader, and make him desire 
a more full account of my doctrine, as well as of the 
arguments, on which it is founded. This request is 
so reasonable, that I cannot refuse complying with it; 
especially as I am hopeful that these principles, the 
more they are examin'd, will acquire the more force 
and evidence. 



204 A TREATISE OF HUMAN NATURE PART III 

There is no question, which on account of its im- 
portance, as well as difficulty, has caus'd more disputes 
both among antient and modern philosophers, than this 
concerning the efficacy of causes, or that quality which 
makes them be followed by their effects. But before 
they enter'd upon these disputes, methinks it wou'd not 
have been improper to have examin'd what idea we 
have of that efficacy, which is the subject of the con- 
troversy. This is what I find principally wanting in 
their reasonings, and what I shall here endeavour to 
supply. 

I begin with observing that the terms of efficacy, 
agency, power, force, energy, necessity, connexion, and 
productive quality, are all nearly synonimous; and 
therefore 'tis an absurdity to employ any of them in 
denning the rest. By this observation we reject at 
once all the vulgar definitions, which philosophers have 
given of power and efficacy; and instead of searching 
for the idea in these definitions, must look for it in the 
impressions, from which it is originally deriv'd. If it 
be a compound idea, it must arise from compound im- 
pressions. If simple, from simple impressions. 

I believe the most general and most popular expli- 
cation of this matter, is to say, 1 that finding from 
experience, that there are several new productions in 
matter, such as the motions and variations of body, 
and concluding that there must somewhere be a power 
capable of producing them, we arrive at last by this 
reasoning at the idea of power and efficacy. But to 
be convinc'd that this explication is more popular than 
philosophical, we need but reflect on two very obvious 
principles. First, That reason alone can never give 
rise to any original idea, and secondly, that reason, as 

1 See Mr. Locke; chapter of Power. 



SECT. XIV BOOK I. OF THE UNDERSTANDING 205 

distinguish'd from experience, can never make us con- 
clude, that a cause or productive quality is absolutely 
requisite to every beginning of existence. Both these 
considerations have been sufficiently explain'd; and 
therefore shall not at present be any farther insisted 
on. 

I shall only infer from them, that since reason can 
never give rise to the idea of efficacy, that idea must 
be deriv'd from experience, and from some particular 
instances of this efficacy, which make their passage 
into the mind by the common channels of sensation or 
reflection. Ideas always represent their objects or 
impressions; and vice versa, there are some objects 
necessary to give rise to every idea. If we pretend, 
therefore, to have any just idea of this efficacy, we 
must produce some instance, wherein the efficacy 
is plainly discoverable to the mind, and its opera- 
tions obvious to our consciousness or sensation. By 
the refusal of this, we acknowledge, that the idea is 
impossible and imaginary ; since the principle of innate 
ideas, which alone can save us from this dilemma, has 
been already refuted, and is now almost universally 
rejected in the learned world. Our present business, 
then, must be to find some natural production, where 
the operation and efficacy of a cause can be clearly 
conceiv'd and comprehended by the mind, without any 
danger of obscurity or mistake. 

In this research we meet with very little encourage- 
ment from that prodigious diversity, which is found in 
the opinions of those philosophers, who have pretended 
to explain the secret force and energy of causes. 1 
There are some, who maintain, that bodies operate by 

1 See Father Malbranche, Book VI., Part II., chap. 3, and the 
illustrations upon it. 



206 A TREATISE OF HUMAN NATURE PART III 

their substantial form; others, by their accidents or 
qualities ; several, by their matter and form ; some, by 
their form and accidents ; others, by certain virtues and 
faculties distinct from all this. All these sentiments 
again are mix'd and vary'd in a thousand different 
ways; and form a strong presumption, that none of 
them have any solidity or evidence, and that the sup- 
position of an efficacy in any of the known qualities 
of matter is entirely without foundation. This pre- 
sumption must encrease upon us, when we consider, 
that these principles of substantial forms, and acci- 
dents, and faculties, are not in reality any of the known 
properties of bodies, but are perfectly unintelligible 
and inexplicable. For 'tis evident philosophers wou'd 
never have had recourse to such obscure, and uncertain 
principles had they met with any satisfaction in such 
as are clear and intelligible ; especially in such an affair 
as this, which must be an object of the simplest under- 
standing, if not of the senses. Upon the whole, we 
may conclude, that 'tis impossible in any one instance 
to shew the principle, in which the force and agency 
of a cause is plac'd ; and that the most refin'd and most 
vulgar understandings are equally at a loss in this 
particular. If any one think proper to refute this 
assertion, he need not put himself to the trouble of 
inventing any long reasonings ; but may at once shew 
us an instance of a cause, where we discover the power 
or operating principle. This defiance we are oblig'd 
frequently to make use of, as being almost the only 
means of proving a negative in philosophy. 

The small success, which has been met with in all 
the attempts to fix this power, has at last oblig'd phi- 
losophers to conclude, that the ultimate force and effi- 
cacy of nature is perfectly unknown to us, and that 



SECT. XIV BOOK I. OF THE UNDERSTANDING 207 

'tis in vain we search for it in all the known qualities 
of matter. In this opinion they are almost unanimous ; 
and 'tis only in the inference they draw from it, that 
they discover any difference in their sentiments. For 
some of them, as the Cartesians in particular, having 
establish'd it as a principle, that we are perfectly ac- 
quainted with the essence of matter, have very natur- 
ally inferr'd, that it is endow'd with no efficacy, and 
that 'tis impossible for it of itself to communicate 
motion, or produce any of those effects, which we 
ascribe to it. As the essence of matter consists in 
extension, and as extension implies not actual motion, 
but only mobility; they conclude, that the energy, 
which produces the motion, cannot lie in the extension. 

This conclusion leads them into another, which 
they regard as perfectly unavoidable. Matter, say 
they, is in itself entirely unactive, and depriv'd of any 
power, by which it may produce, or continue, or com- 
municate motion: But since these effects are evident 
to our senses, and since the power, that produces them, 
must be plac'd somewhere, it must lie in the Deity, 
or that divine being, who contains in his nature all 
excellency and perfection. Tis the deity, therefore, 
who is the prime mover of the universe, and who not 
only first created matter, and gave it it's original im- 
pulse, but likewise by a continu'd exertion of omnipo- 
tence, supports its existence, and successively bestows 
on it all those motions, and configurations, and quali- 
ties, with which it is endow'd. 

This opinion is certainly very curious, and well 
worth our attention; but 'twill appear superfluous to 
examine it in this place, if we reflect a moment on our 
present purpose in taking notice of it. We have estab- 
lish'd it as a principle, that as all ideas are deriv'd 



208 A TREATISE OF HUMAN NATURE PART III 

from impressions, or some precedent perceptions, 'tis 
impossible we can have any idea of power and efficacy, 
unless some instances can be produc'd, wherein this 
power is perceiv'd to exert itself. Now as these in- 
stances can never be discover'd in body, the Cartesians, 
proceeding upon their principle of innate ideas, have 
had recourse to a supreme spirit or deity, whom they 
consider as the only active being in the universe, and 
as the immediate cause of every alteration in matter. 
But the principle of innate ideas being allow'd to be 
false, it follows, that the supposition of a deity can 
serve us in no stead, in accounting for that idea of 
agency, which we search for in vain in all the objects 
which are presented to our senses, or which we are 
internally conscious of in our own minds. For if 
every idea be deriv'd from an impression, the idea of 
a deity proceeds from the same origin; and if no 
impression, either of sensation or reflection, implies 
any force or efficacy, 'tis equally impossible to discover 
or even imagine any such active principle in the deity. 
Since these philosophers, therefore, have concluded, 
that matter cannot be endow'd with any efficacious 
principle, because 'tis impossible to discover in it such 
a principle; the same course of reasoning shou'd de- 
termine them to exclude it from the supreme being. 
Or if they esteem that opinion absurd and impious, as 
it really is, I shall tell them how they may avoid it; 
and that is, by concluding from the very first, that 
they have no adequate idea of power or efficacy in any 
object; since neither in body nor spirit, neither in 
superior nor inferior natures, are they able to discover 
one single instance of it. 

The same conclusion is unavoidable upon the hy- 
pothesis of those, who maintain the efficacy of second 



SECT. XIV BOOK I. OF THE UNDERSTANDING 209 

causes, and attribute a derivative, but a real power and 
energy to matter. For as they confess, that this energy 
lies not in any of the known qualities of matter, the 
difficulty still remains concerning the origin of its idea. 
If we have really an idea of power, we may attribute 
power to an unknown quality: But as 'tis impossible, 
that that idea can be deriv'd from such a quality, and 
as there is nothing in known qualities, which can pro- 
duce it; it follows that we deceive ourselves, when we 
imagine we are possest of any idea of this kind, after 
the manner we commonly understand it. All ideas are 
deriv'd from, and represent impressions. We never 
have any impression, that contains any power or effi- 
cacy. We never therefore have any idea of power. 

It has been establish'd as a certain principle, that 
general or abstract ideas are nothing but individual 
ones taken in a certain light, and that, in reflecting 
on any object, 'tis as impossible to exclude from our 
thought all particular degrees of quantity and quality 
as from the real nature of things. If we be possest, 
therefore, of any idea of power in general, we must 
also be able to conceive some particular species of it; 
and as power cannot subsist alone, but is always re- 
garded as an attribute of some being or existence, we 
must be able to place this power in some particular 
being, and conceive that being as endow'd with a real 
force and energy, by which such a particular effect 
necessarily results from its operation. We must dis- 
tinctly and particularly conceive the connexion betwixt 
the cause and effect, and be able to pronounce, from 
a simple view of the one, that it must be follow'd or 
preceded by the other. This is the true manner of 
conceiving a particular power in a particular body: 
and a general idea being impossible without an indi- 



2io A TREATISE OF HUMAN NATURE PART III 

vidual; where the latter is impossible, 'tis certain the 
former can never exist. Now nothing is more evident, 
than that the human mind cannot form such an idea 
of two objects, as to conceive any connexion betwixt 
them, or comprehend distinctly that power and efficacy, 
by which they are united. Such a connexion wou'd 
amount to a demonstration, and wou'd imply the abso- 
lute impossibility for the one object not to follow, or 
to be conceiv'd not to follow upon the other: Which 
kind of connexion has already been rejected in all 
cases. If any one is of a contrary opinion, and thinks 
he has attain'd a notion of power in any particular 
object, I desire he may point out to me that object. 
But till I meet with such-a-one, which I despair of, I 
cannot forbear concluding, that since we can never 
distinctly conceive how any particular power can pos- 
sibly reside in any particular object, we deceive our- 
selves in imagining we can form any such general 
idea. 

Thus upon the whole we may infer, that when we 
talk of any being, whether of a superior or inferior 
nature, as endow'd with a power or force, proportion'd 
to any effect ; when we speak of a necessary connexion 
betwixt objects, and suppose, that this connexion de- 
pends upon an efficacy or energy, with which any of 
these objects are endow'd; in all these expressions, so 
apply' d, we have really no distinct meaning, and make 
use only of common words, without any clear and 
determinate ideas. But as 'tis more probable, that 
these expressions do here lose their true meaning by 
being wrong apply 'd, than that they never have any 
meaning; 'twill be proper to bestow another consider- 
ation on this subject, to see if possibly we can discover 
the nature and origin of those ideas, we annex to them. 



SECT. XIV BOOK I. OF THE UNDERSTANDING 211 

Suppose two objects to be presented to us, of which 
the one is the cause and the other the effect ; 'tis plain, 
that from the simple consideration of one, or both 
these objects we never shall perceive the tie, by which 
they are united, or be able certainly to pronounce, that 
there is a connexion betwixt them. Tis not, there- 
fore, from any one instance, that we arrive at the 
idea of cause and effect, of a necessary connexion of 
power, of force, of energy, and of efficacy. Did we 
never see any but particular conjunctions of objects, 
entirely different from each other, we shou'd never be 
able to form any such ideas. 

But again; suppose we observe several instances, 
in which the same objects are always conjoin'd to- 
gether, we immediately conceive a connexion betwixt 
them, and begin to draw an inference from one to 
another. This multiplicity of resembling instances, 
therefore, constitutes the very essence of power or 
connexion, and is the source, from which the idea of 
it arises. In order, then, to understand the idea of 
power, we must consider that multiplicity; nor do I 
ask more to give a solution of that difficulty, which 
has so long perplex'd us. For thus I reason. The 
repetition of perfectly similar instances can never alone 
give rise to an original idea, different from what is to 
be found in any particular instance, as has been ob- 
serv'd, and as evidently follows from our fundamen- 
tal principle, that all ideas are copy'd from impressions. 
Since therefore the idea of power is a new original 
idea, not to be found in any one instance, and which 
yet arises from the repetition of several instances, it 
follows, that the repetition alone has not that effect, 
but must either discover or produce something new, 
which is the source of that idea. Did the repetition 



212 A TREATISE OF HUMAN NATURE PART III 

neither discover nor produce any thing new, our ideas 
might be multiply'd by it, but wou'd not be enlarg'd 
above what they are upon the observation of one single 
instance. Every enlargement, therefore, (such as the 
idea of power or connexion) which arises from the 
multiplicity of similar instances, is copy'd from some 
effects of the multiplicity, and will be perfectly under- 
stood by understanding these effects. Wherever we 
find any thing new to be discover'd or produc'd by the 
repetition, there we must place the power, and must 
never look for it in any other object. 

But 'tis evident, in the first place, that the repeti- 
tion of like objects in like relations of succession and 
contiguity discovers nothing new in any one of them; 
since we can draw no inference from it, nor make it a 
subject either of our demonstrative or probable rea- 
sonings ; x as has been already prov'd. Nay suppose we 
cou'd draw an inference, 'twou'd be of no consequence 
in the present case; since no kind of reasoning can 
give rise to a new idea, such as this of power is ; but 
wherever we reason, we must antecedently be possest 
of clear ideas, which may be the objects of our reason- 
ing. The conception always precedes the understand- 
ing; and where the one is obscure, the other is uncer- 
tain; where the one fails, the other must fail also. 

Secondly, 'Tis certain that this repetition of similar 
objects in similar situations produces nothing new 
either in these objects, or in any external body. For 
'twill readily be allow'd, that the several instances we 
have of the conjunction of resembling causes and 
effects are in themselves entirely independent, and that 
the communication of motion, which I see result at 
present from the shock of two billiard-balls, is totally 

1 Sect. 6. 



SECT. XIV BOOK I. OF THE UNDERSTANDING 213 

distinct from that which I saw result from such an 
impulse a twelve-month ago. These impulses have no 
influence on each other. They are entirely divided by 
time and place; and the one might have existed and 
communicated motion, tho' the other never had been 
in being. 

There is, then, nothing new either discover'd or 
produc'd in any objects by their constant conjunction, 
and by the uninterrupted resemblance of their rela- 
tions of succession and contiguity. But 'tis from this 
resemblance, that the ideas of necessity, of power, and 
of efficacy, are deriv'd. These ideas, therefore, rep- 
resent not any thing, that does or can belong to the 
objects, which are constantly conjoin'd. This is an 
argument, which, in every view we can examine it, 
will be found perfectly unanswerable. Similar in- 
stances are still the first source of our idea of power 
or necessity ; at the same time that they have- no influ- 
ence by their similarity either on each other, or on any 
external object. We must therefore, turn ourselves 
to some other quarter to seek the origin of that idea. 

Tho' the several resembling instances, which give 
rise to the idea of power, have no influence on each 
other, and can never produce any new quality in the 
object, which can be the model of that idea, yet the 
observation of this resemblance produces a new im- 
pression in the mind, which is its real model. For 
after we have observ'd the resemblance in a sufficient 
number of instances, we immediately feel a determin- 
ation of the mind to pass from one object to its usual 
attendant, and to conceive it in a stronger light upon 
account of that relation. This determination is the 
only effect of the resemblance ; and therefore must be 
the same with power or efficacy, whose idea is de- 



2i 4 A TREATISE OF HUMAN NATURE PART 111 

riv'd from the resemblance. The several instances of 
resembling conjunctions lead us into the notion of 
power and necessity. These instances are in them- 
selves totally distinct from each other, and have no 
union but in the mind, which observes them, and col- 
lects their ideas. Necessity, then, is the effect of this 
observation, and is nothing but an internal impres- 
sion of the mind, or a determination to carry our 
thoughts from one object to another. Without con- 
sidering it in this view, we can never arrive at the most 
distant notion of it, or be able to attribute it either 
to external or internal objects, to spirit or body, to 
causes or effects. 

The necessary connexion betwixt causes and effects 
is the foundation of our inference from one to the 
other. The foundation of our inference is the tran- 
sition arising from the accustom'd union. These are, 
therefore, the same. 

The idea of necessity arises from some impression. 
There is no impression convey'd by our senses, which 
can give rise to that idea. It must, therefore, be 
deriv'd from some internal impression, or impression 
of reflexion. There is no internal impression, which 
has any relation to the present business, but that pro- 
pensity, which custom produces, to pass from an object 
to the idea of its usual attendant. This therefore is 
the essence of necessity. Upon the whole, necessity 
is something, that exists in the mind, not in objects; 
nor is it possible for us ever to form the most distant 
idea of it, consider'd as a quality in bodies. Either 
we have no idea of necessity, or necessity is nothing 
but that determination of the thought to pass from 
causes to effects and from effects to causes, according 
to their experienc'd union. 



SECT. XIV BOOK I. OF THE UNDERSTANDING 215 

Thus as the necessity, which makes two times two 
equal to four, or three angles of a triangle equal to 
two right ones, lies only in the act of the understand- 
ing, by which we consider and compare these ideas; 
in like manner the necessity or power, which unites 
causes and effects, lies in the determination of the 
mind to pass from the one to the other. The efficacy 
or energy of causes is neither plac'd in the causes 
themselves, nor in the deity, nor in the concurrence of 
these two principles ; but belongs entirely to the soul, 
which considers the union of two or more objects in 
all past instances. 'Tis here that the real power of 
causes is plac'd, along with their connexion and neces- 
sity. 

I am sensible, that of all the paradoxes, which I 
have had, or shall hereafter have occasion to advance 
in the course of this treatise, the present one is the 
most violent, and that 'tis merely by dint of solid 
proof and reasoning I can ever hope it will have ad- 
mission, and overcome the inveterate prejudices of 
mankind. Before we are reconcil'd to this doctrine, 
how often must we repeat to ourselves, that the simple 
view of any two objects or actions, however related, 
can never give us any idea of power, or of a connexion 
betwixt them : that this idea arises from the repetition 
of their union : that the repetition neither discovers nor 
causes any thing in the objects, but has an influence 
only on the mind, by that customary transition it pro- 
duces : that this customary transition is, therefore, the 
same with the power and necessity; which are conse- 
quently qualities of perceptions, not of objects, and 
are internally felt by the soul, and not perceiv'd exter- 
nally in bodies? There is commonly an astonishment 
attending every thing extraordinary; and this astonish- 



216 A TREATISE OF HUMAN NATURE PART III 

ment changes immediately into the highest degree of 
esteem or contempt, according as we approve or dis- 
approve of the subject. I am much afraid, that tho' 
the foregoing reasoning appears to me the shortest 
and most decisive imaginable; yet with the generality 
of readers the biass of the mind will prevail, and give 
them a prejudice against the present doctrine. 

This contrary biass is easily accounted for. Tis a 
common observation, that the mind has a great pro- 
pensity to spread itself on external objects, and to 
conjoin with them any internal impressions, which 
they occasion, and which always make their appear- 
ance at the same time that these objects discover them- 
selves to the senses. Thus as certain sounds and smells 
are always found to attend certain visible objects, we 
naturally imagine a conjunction, even in place, betwixt 
the objects and qualities, tho' the qualities be of such 
a nature as to admit of no such conjunction, and really 
exist no where. But of this more fully 1 hereafter. 
Mean while 'tis sufficient to observe, that the same pro- 
pensity is the reason, why we suppose necessity and 
power to lie in the objects we consider, not in our 
mind, that considers them; notwithstanding it is not 
possible for us to form the most distant idea of that 
quality, when it is not taken for the determination of 
the mind, to pass from the idea of an object to that 
of its usual attendant. 

But tho' this be the only reasonable account we 
can give of necessity, the contrary notion is so riveted 
in the mind from the principles above-mention'd, that 
I doubt not but my sentiments will be treated by many 
as extravagant and ridiculous. What! the efficacy of 
causes lie in the determination of the mind ! As if 

1 Part IV., Sect. 5. 



SECT. XIV BOOK I. OF THE UNDERSTANDING 217 

causes did not operate entirely independent of the 
mind, and wou'd not continue their operation, even 
tho' there was no mind existent to contemplate them, 
or reason concerning them. Thought may well depend 
on causes for its operation, but not causes on thought. 
This is to reverse the order of nature, and make that 
secondary, which is really primary. To every opera- 
tion there is a power proportion'd ; and this power 
must be plac'd on the body, that operates. If we 
remove the power from one cause, we must ascribe it 
to another: But to remove it from all causes, and 
bestow it on a being, that is no ways related to the 
cause or effect, but by perceiving them, is a gross 
absurdity, and contrary to the most certain principles 
of human reason. 

I can only reply to all these arguments, that the 
case is here much the same, as if a blind man shou'd 
pretend to find a great many absurdities in the sup- 
position, that the colour of scarlet is not the same with 
the sound of a trumpet, nor light the same with solid- 
ity. If we have really no idea of a power or efficacy 
in any object, or of any real connexion betwixt causes 
and effects, 'twill be to little purpose to prove, that 
an efficacy is necessary in all operations. We do not 
understand our own meaning in talking so, but igno- 
rantly confound ideas, which are entirely distinct from 
each other. I am, indeed, ready to allow, that there 
may be several qualities both in material and imma- 
terial objects, with which we are utterly unacquainted; 
and if we please to call these power or efficacy, 
'twill be of little consequence to the world. But 
when, instead of meaning these unknown quali- 
ties, we make the terms of power and efficacy signify 
something, of which we have a clear idea, and which is 



218 A TREATISE OF HUMAN NATURE PART III 

incompatible with those objects, to which we apply it, 
obscurity and error begin then to take place, and we 
are led astray by a false philosophy. This is the case, 
when we transfer the determination of the thought to 
external objects, and suppose any real intelligible con- 
nexion betwixt them; that being a quality, which can 
only belong to the mind that considers them. 

As to what may be said, that the operations of 
nature are independent of our thought and reasoning, 
I allow it; and accordingly have observ'd, that objects 
bear to each other the relations of contiguity and suc- 
cession; that like objects may be observ'd in several 
instances to have like relations; and that all this is 
independent of, and antecedent to the operations of 
the understanding. But if we go any farther, and 
ascribe a power or necessary connexion to these ob- 
jects; this is what we can never observe in them, but 
must draw the idea of it from what we feel internally 
in contemplating them. And this I carry so far, that 
I am ready to convert my present reasoning into an 
instance of it, by a subtility, which it will not be diffi- 
cult to comprehend. 

When any object is presented to us, it immediately 
conveys to the mind a lively idea of that object, which 
is usually found to attend it; and this determination 
of the mind forms the necessary connexion of these 
objects. But when we change the point of view, from 
the objects to the perceptions; in that case the impres- 
sion is to be considered as the cause, and the lively 
idea as the effect; and their necessary connexion is 
that new determination, which we feel to pass from 
the idea of the one to that of the other. The uniting 
principle among our internal perceptions is as unin- 
telligible as that among external objects, and is not 



SECT. XIV BOOK L OF THE UNDERSTANDING 219 

known to us any other way than by experience. Now 
the nature and effects of experience have been already 
sufficiently examin'd and explain'd. It never gives us 
any insight into the internal structure or operating 
principle of objects, but only accustoms the mind to 
pass from one to another. 

Tis now time to collect all the different parts of 
this reasoning, and by joining them together form an 
exact definition of the relation of cause and effect, 
which makes the subject of the present enquiry. This 
order wou'd not have been excusable, of first examin- 
ing our inference from the relation before we 
had explain'd the relation itself, had it been pos- 
sible to proceed in a different method. But as the 
nature of the relation depends so much on that of the 
inference, we have been oblig'd to advance in this 
seemingly preposterous manner, and make use of 
terms before we were able exactly to define them, or 
fix their meaning. We shall now correct this fault 
by giving a precise definition of cause and effect. 

There may two definitions be given of this relation, 
which are only different, by their presenting a different 
view of the same object, and making us consider it 
either as a philosophical or as a natural relation; 
either as a comparison of two ideas, or as an associa- 
tion betwixt them. We may define a cause to be 'An 
object precedent and contiguous to another, and where 
all the objects resembling the former are plac'd in like 
relations of precedency and contiguity to those objects, 
that resemble the latter.' If this definition be esteem'd 
defective, because drawn from objects foreign to the 
cause, we may substitute this other definition in its 
place, viz. 'A cause is an object precedent and con- 
tiguous to another, and so united with it, that the idea 



220 A TREATISE OF HUMAN NATURE. PART III 

of the one determines the mind to form the idea of 
the other, and the impression of the one to form a 
more lively idea of the other.' Shou'd this definition 
also be rejected for the same reason, I know no other 
remedy, than that the persons, who express this deli- 
cacy, should substitute a juster definition in its place. 
But for my part I must own my incapacity for 
such an undertaking. When I examine with the ut- 
most accuracy those objects, which are commonly 
denominated causes and effects, I find, in considering 
a single instance, that the one object is precedent and 
contiguous to the other; and in inlarging my view to 
consider several instances, I find only, that like objects 
are constantly plac'd in like relations of succession and 
contiguity. Again, when I consider the influence of 
this constant conjunction, I perceive, that such a rela- 
tion can never be an object of reasoning, and can never 
operate upon the mind, but by means of custom, which 
determines the imagination to make a transition from 
the idea of one object to that of its usual attendant, 
and from the impression of one to a more lively idea 
of the other. However extraordinary these sentiments 
may appear, I think it fruitless to trouble myself with 
any farther enquiry or reasoning upon the subject, but 
shall repose myself on them as on establish'd maxims. 
'Twill only be proper, before we leave this subject, 
to draw some corollaries from it, by which we may 
remove several prejudices and popular errors, that 
have very much prevail'd in philosophy. First, We 
may learn from the foregoing doctrine, that all causes 
are of the same kind, and that in particular there is 
no foundation for that distinction, which we sometimes 
make betwixt efficient causes, and causes sine qua non; 
or betwixt efficient causes, and formal, and material, 



SECT. XIV BOOK I. OF THE UNDERSTANDING 221 

and exemplary, and final causes. For as our idea of 
efficiency is deriv'd from the constant conjunction of 
two objects, wherever this is observ'd, the cause is 
efficient; and where it is not, there can never be a 
cause of any kind. For the same reason we must 
reject the distinction betwixt cause and occasion, when 
suppos'd to signify any thing essentially different from 
each other. If constant conjunction be imply'd in 
what we call occasion, 'tis a real cause. If not, 'tis 
no relation at all, and cannot give rise to any argu- 
ment or reasoning. 

Secondly, The same course of reasoning will make 
us conclude, that there is but one kind of necessity, 
as there is but one kind of cause, and that the common 
distinction betwixt moral and physical necessity is 
without any foundation in nature. This clearly ap- 
pears from the precedent explication of necessity. 'Tis 
the constant conjunction of objects, along with the 
determination of the mind, which constitutes a physi- 
cal necessity: And the removal of these is the same 
thing with chance. As objects must either be con- 
joint or not, and as the mind must either be deter- 
min'd or not to pass from one object to another, 'tis 
impossible to admit of any medium betwixt chance and 
an absolute necessity. In weakening this conjunction 
and determination you do not change the nature of 
the necessity; since even in the operation of bodies, 
these have different degrees of constancy and force, 
without producing a different species of that relation. 

The distinction, which we often make betwixt 
power and the exercise of it, is equally without foun- 
dation. 

Thirdly, We may now be able fully to overcome 
all that repugnance, which 'tis so natural for us to 



222 A TREATISE OF HUMAN NATURE. PART III 

entertain against the foregoing reasoning, by which 
we endeavour'd to prove, that the necessity of a cause 
to every beginning of existence is not founded on any 
arguments either demonstrative or intuitive. Such an 
opinion will not appear strange after the foregoing 
definitions. If we define a cause to be an object pre- 
cedent and contiguous to another, and where all the 
objects resembling the former are plac'd in a like 
relation of priority and contiguity to those objects, that 
resemble the latter; we may easily conceive, that there 
is no absolute nor metaphysical necessity, that every 
beginning of existence shou'd be attended with such 
an object. If we define a cause to be, An object pre- 
cedent and contiguous to another, and so united with it 
in the imagination, that the idea of the one determines 
the mind to form the idea of the other, and the im- 
pression of the one to form a more lively idea of the 
other; we shall make still less difficulty of assenting to 
this opinion. Such an influence on the mind is in 
itself perfectly extraordinary and incomprehensible; 
nor can we be certain of its reality, but from experi- 
ence and observation. 

I shall add as a fourth corrollary, that we can never 
have reason to believe that any object exists, of which 
we cannot form an idea. For as all our reasonings 
concerning existence are deriv'd from causation, and 
as all our reasonings concerning causation are deriv'd 
from the experienc'd conjunction of objects, not from 
any reasoning or reflexion, the same experience must 
give us a notion of these objects, and must remove all 
mystery from our conclusions. This is so evident, 
that 'twou'd scarce have merited our attention, were 
it not to obviate certain objections of this kind, which 
might arise against the following reasonings concern- 



SECT. XIV BOOK I. OF THE UNDERSTANDING 223 

ing matter and substance. I need not observe, that a 
full knowledge of the object is not requisite, but only 
of those qualities of it, which we believe to exist. 



THE DOCTRINE OF SUBSTANCE 



SELECTIONS FROM 
BOOK /., PARTS /., //., IF. 



PART I. 

OF IDEAS, THEIR ORIGIN, COMPOSITION, 
CONNEXION, ABSTRACTION. 



* 


* 


* * 


* 


* 


* 


* * 
Section VI. 


* 



Of modes and substances. 

I wou'd fain ask those philosophers, who found so 
much of their reasonings on the distinction of sub- 
stance and accident, and imagine we have clear ideas 
of each, whether the idea of substance be deriv'd from 
the impressions of sensation or reflexion? If it be 
convey'd to us by our senses, I ask, which of them; 
and after what manner ? If it be perceiv'd by the eyes, 
it must be colour; if by the ears, a sound; if by the 
palate, a taste; and so of the other senses. But I 
believe none will assert, that substance is either a 
colour, or sound, or a taste. The idea of substance 
must therefore be deriv'd from an impression of re- 
flexion, if it really exist. But the impressions of re- 
flexion resolve themselves into our passions and emo- 
tions ; none of which can possibly represent a sub- 
stance. We have therefore no idea of substance, dis- 
tinct from that of a collection of particular qualities, 
nor have we any other meaning when we either talk 
or reason concerning it. 

The idea of a substance as well as that of a mode, 
is nothing but a collection of simple ideas, that are 
united by the imagination, and have a particular name 



228 A TREATISE OF HUMAN NATURE PART I 

assigned them, by which we are able to recall, either 
to ourselves or others, that collection. But the differ- 
ence betwixt these ideas consists in this, that the par- 
ticular qualities, which form a substance, are com- 
monly refer'd to an unknown something, in which they 
are supposed to inhere ; or granting this fiction should 
not take place, are at least supposed to be closely and' 
inseparably connected by the relations of contiguity 
and causation. The effect of this is, that whatever 
new simple quality we discover to have the same con- 
nexion with the rest, we immediately comprehend it 
among them, even tho' it did not enter into the first 
conception of the substance. Thus our idea of gold 
may at first be a yellow colour, weight, malleableness, 
fusibility; but upon the discovery of its dissolubility 
in aqua regia, we join that to the other qualities, and 
suppose it to belong to the substance as much as if 
its idea had from the beginning made a part of the 
compound one. The principle of union being regarded 
as the chief part of the complex idea, gives entrance 
to whatever quality afterwards occurs, and is equally 
comprehended by it, as are the others, which first pre- 
sented themselves. 

That this cannot take place in modes, is evident 
from considering their nature. The simple ideas of 
which modes are formed, either represent qualities, 
which are not united by contiguity and causation, but 
are dispers'd in different subjects; or if they be all 
united together, the uniting principle is not regarded 
as the foundation of the complex idea. The idea of a 
dance is an instance of the first kind of modes ; that of 
beauty of the second. The reason is obvious, why such 
complex ideas cannot receive any new idea, without 
changing the name, which distinguishes the mode. 



PART II. 
OF THE IDEAS OF SPACE AND TIME. 

Section VI. 
Of the idea of existence, and of external existence. 

It may not be amiss, before we leave this subject, 
to explain the ideas of existence and of external exist- 
ence; which have their difficulties, as well as the ideas 
of space and time. By this means we shall be the better 
prepar'd for the examination of knowledge and prob- 
ability, when we understand perfectly all those par- 
ticular ideas, which may enter into our reasoning. 

There is no impression nor idea of any kind, of 
which we have any consciousness or memory, that is 
not conceiv'd as existent; and 'tis evident, that from 
this consciousness the most perfect idea and assur- 
ance of being is deriv'd. From hence we may form a 
dilemma, the most clear and conclusive that can be 
imagin'd, viz. that since we never remember any idea 
or impression without attributing existence to it, the 
idea of existence must either be deriv'd from a distinct 
impression, conjoin'd with every perception or object 
of our thought, or must be the very same with the idea 
of the perception or object. 

As this dilemma is an evident consequence of the 
principle, that every idea arises from a similar impres- 



230 A TREATISE OF HUMAN NATURE PART II 

sion, so our decision betwixt the propositions of the 
dilemma is no more doubtful. So far from there being 
any distinct impression, attending every impression 
and every idea, that I do not think there are any two 
distinct impressions, which are inseparably conjoin'd. 
Tho' certain sensations may at one time be united, we 
quickly find they admit of a separation, and may be 
presented apart. And thus, tho' every impression and 
idea we remember be consider'd as existent, the idea 
of existence is not deriv'd from any particular impres- 
sion. 

The idea of existence, then, is the very same with 
the idea of what we conceive to be existent. To reflect 
on any thing simply, and to reflect on it as existent, 
are nothing different from each other. That idea, 
when conjoin'd with the idea of any object, makes no 
addition to it. Whatever we conceive, we conceive to 
be existent. Any idea we please to form is the idea 
of a being; and the idea of a being is any idea we 
please to form. 

Whoever opposes this, must necessarily point out 
that distinct impression, from which the idea of entity 
is deriv'd, and must prove, that this impression is in- 
separable from every perception we believe to be exist- 
ent. This we may without hesitation conclude to be 
impossible. 

Our foregoing 1 reasoning concerning the distinc- 
tion of ideas without any real difference will not here 
serve us in any stead. That kind of distinction is 
founded on the different resemblances, which the same 
simple idea may have to several different ideas. But 
no object can be presented resembling some object 
with respect to its existence, and different from others 

1 Part I., Sect. 7. 



SECT. VI BOOK I. OF THE UNDERSTANDING 231 

in the same particular; since every object, that is pre- 
sented, must necessarily be existent. 

A like reasoning will account for the idea of exter- 
nal existence. We may observe, that 'tis universally 
allow'd by philosophers, and is besides pretty obvious 
of itself, that nothing is ever really present with the 
mind but its perceptions or impressions and ideas, and 
that external objects become known to us only by those 
perceptions they occasion. To hate, to love, to think, 
to feel, to see ; all this is nothing but to perceive. 

Now since nothing is ever present to the mind but 
perceptions, and since all ideas are deriv'd from some- 
thing antecedently present to the mind ; it follows, that 
'tis impossible for us so much as to conceive or form 
an idea of any thing specifically different from 
ideas and impressions. Let us fix our attention out 
of ourselves as much as possible: Let us chace our 
imagination to the heavens, or to the utmost limits of 
the universe; we never really advance a step beyond 
ourselves, nor can conceive any kind of existence, 
but those perceptions, which have appear'd in that nar- 
row compass. This is the universe of the imagination, 
nor have we any idea but what is there produc'd. 

The farthest we can go towards a conception of 
external objects, when suppos'd specifically different 
from our perceptions, is to form a relative idea of 
them, without pretending to comprehend the related 
objects. Generally speaking we do not suppose them 
specifically different ; but only attribute to them differ- 
ent relations, connexions and durations. But of this 
more fully hereafter. 1 

****** 
****** 
1 Part IV., Sect. 2. 



PART IV. 

OF THE SCEPTICAL AND OTHER SYSTEMS 

OF PHILOSOPHY. 

SfS 3|C 5}C 5j£ 5fC «|S 

****** 

Section II. 
0/ scepticism with regard to the senses. 

Thus the sceptic still continues to reason and be- 
lieve, even tho' he asserts, that he cannot defend his 
reason by reason ; and by the same rule he must assent 
to the principle concerning the existence of body, tho' 
he cannot pretend by any arguments of philosophy to 
maintain its veracity. Nature has not left this to his 
choice, and has doubtless esteem'd it an affair of too 
great importance to be trusted to our uncertain rea- 
sonings and speculations. We may well ask, What 
causes induce us to believe in the existence of body? 
but 'tis vain to ask, Whether there be body or not? 
That is a point, which we must take for granted in all 
our reasonings. 

The subject, then, of our present enquiry is con- 
cerning the causes which induce us to believe in the 
existence of body; and my reasonings on this head I 
shall begin with a distinction, which at first sight may 
seem superfluous, but which will contribute very much 
to the perfect understanding of what follows. We 
ought to examine apart those two questions, which are 
commonly confounded together, vis. Why we attribute 
a continued existence to objects, even when they are 



SECT. II BOOK I. OF THE UNDERSTANDING 233 

not present to the senses; and why we suppose them 
to have an existence distinct from the mind and per- 
ception. Under this last head I comprehend their 
situation as well as relations, their external position 
as well as the independence of their existence and 
operation. These two questions concerning the con- 
tinued and distinct existence of body are intimately 
connected together. For if the objects of our senses 
continue to exist, even when they are not perceiv'd, 
their existence is of course independent of and dis- 
tinct from the perception; and vice versa, if their 
existence be independent of the perception and dis- 
tinct from it, they must continue to exist, even tho' 
they be not perceiv'd. But tho' the decision of the one 
question decides the other; yet that we may the more 
easily discover the principles of human nature, from 
whence the decision arises, we shall carry along with 
us this distinction, and shall consider, whether it be 
the senses, reason, or the imagination, that produces 
the opinion of a continued or of a distinct existence. 
These are the only questions, that are intelligible on 
the present subject. For as to the notion of external 
existence, when taken for something specifically dif- 
ferent from our perceptions, 1 we have already shewn 
its absurdity. 

To begin with the senses, 'tis evident these facul- 
ties are incapable of giving rise to the notion of the 
continued existence of their objects, after they no 
longer appear to the senses. For that is a contradic- 
tion in terms, and supposes that the senses continue to 
operate, even after they have ceas'd all manner of 
operation. These faculties, therefore, if they have any 
influence in the present case, must produce the opinion 

1 Part II., Sect. 6. 



234 A TREATISE OF HUMAN NATURE PART IV 

Df a distinct, not of a continue existence ; and in order 
to that, must present their impressions either as images 
and representations, or as these very distinct and 
external existences. 

That our senses offer not their impressions as the 
images of something distinct, or independent, and ex- 
ternal, is evident; because they convey to us nothing 
but a single perception, and never give us the least 
intimation of any thing beyond. A single perception 
can never produce the idea of a double existence, but 
by some inference either of the reason or imagination. 
When the mind looks farther than what immediately 
appears to it, its conclusions can never be put to the 
account of the senses; and it certainly looks farther, 
when from a single perception it infers a double exist- 
ence, and supposes the relations of resemblance and 
causation betwixt them. 



But tho' we are led after this manner, by the nat- 
ural propensity of the imagination, to ascribe a con- 
tinu'd existence to those sensible objects or percep- 
tions, which we find to resemble each other in their 
interrupted appearance; yet a very little reflection and 
philosophy is sufficient to make us perceive the fallacy 
of that opinion. I have already observ'd, that there 
is an intimate connexion betwixt those two principles, 
of a continu'd and of a distinct or independent exist- 
ence, and that we no sooner establish the one than the 
other follows, as a necessary consequence. 'Tis the 
opinion of a continu'd existence, which first takes place, 
and without much study or reflection draws the other 
along with it, wherever the mind follows its first and 



SECT. II BOOK I. OF THE UNDERSTANDING 235 

most natural tendency. But when we compare experi- 
ments, and reason a little upon them, we quickly per- 
ceive, that the doctrine of the independent existence 
of our sensible perceptions is contrary to the plainest 
experience. This leads us backward upon our foot- 
steps to perceive our error in attributing a continu'd 
existence to our perceptions, and is the origin of many 
very curious opinions, which we shall here endeavour 
to account for. 

'Twill first be proper to observe a few of those 
experiments, which convince us, that our perceptions 
are not possest of any independent existence. When 
we press one eye with a finger, we immediately per- 
ceive all the objects to become double, and one half 
of them to be remov'd from their common and natural 
position. But as we do not attribute a continu'd exist- 
ence to both these perceptions, and as they are both 
of the same nature, we clearly perceive, that all our 
perceptions are dependent on our organs, and the dis- 
position of our nerves and animal spirits. This opinion 
is confirm'd by the seeming encrease and diminution 
of objects, according to their distance; by "the appar- 
ent alterations in their figure; by the changes in their 
colour and other qualities from our sickness and dis- 
tempers ; and by an infinite number of other experi- 
ments of the same kind; from all which we learn, 
that our sensible perceptions are not possest of any 
distinct or independent existence. 

The natural consequence of this reasoning shou'd 
be, that our perceptions have no more a continu'd than 
an independent existence ; and indeed philosophers 
have so far run into this opinion, that they change 
their system, and distinguish, (as we shall do for the 
future) betwixt perceptions and objects, of which the 



236 A TREATISE OF HUMAN NATURE PART IV 

former are suppos'd to be interrupted, and perishing, 
and different at every different return ; the latter to be 
uninterrupted, and to preserve a continu'd existence and 
identity. But however philosophical this new system 
may be esteem'd, I assert that 'tis only a palliative rem- 
edy, and that it contains all the difficulties of the vulgar 
system, with some others, that are peculiar to itself. 
There are no principles either of the understanding 
or fancy, which lead us directly to embrace this opinion 
of the double existence of perceptions and objects, nor 
can we arrive at it but by passing thro' the common 
hypothesis of the identity and continuance of our inter- 
rupted perceptions. Were we not first perswaded, 
that our perceptions are our only objects, and continue 
to exist even when they no longer make their appear- 
ance to the senses, we shou'd never be led to think, 
that our perceptions and objects are different, and that 
our objects alone preserve a continu'd existence. 'The 
latter hypothesis has no primary recommendation 
either to reason or the imagination, but acquires all 
its influence on the imagination from the former.' 
This proposition contains two parts, which we shall 
endeavour to prove as distinctly and clearly, as such 
abstruse subjects will permit. 

As to the first part of the proposition, that this 
philosophical hypothesis has no primary recommenda- 
tion, either to reason or the imagination, we may soon 
satisfy ourselves with regard to reason by the follow- 
ing reflections. The only existences, of which we are 
certain, are perceptions, which being immediately pres- 
ent to us by consciousness, command our strongest 
assent, and are the first foundation of all our conclu- 
sions. The only conclusion we can draw from the 
existence of one thing to that of another, is by means 



SECT. II BOOK I. OF THE UNDERSTANDING 237 

of the relation of cause and effect, which shews, that 
there is a connexion betwixt them, and that the exist- 
ence of one is dependent on that of the other. The 
idea of this relation is deriv'd from past experience, 
by which we find, that two beings are constantly con- 
joint together, and are always present at once to the 
mind. But as no beings are ever present to the mind 
but perceptions ; it follows that we may observe a con- 
junction or a relation of cause and effect between dif- 
ferent perceptions, but can never observe it between 
perceptions and objects. 'Tis impossible, therefore, 
that from the existence or any of the qualities of the 
former, we can ever form any conclusion concerning 
the existence of the latter, or ever satisfy our reason 
in this particular. 

'Tis no less certain, that this philosophical system 
has no primary recommendation to the imagination, 
and that that faculty wou'd never, of itself, and by its 
original tendency, have fallen upon such a principle. 
I confess it will be somewhat difficult to prove this 
to the full satisfaction of the reader ; because it implies 
a negative, which in many cases will not admit of any 
positive proof. If any one wou'd take the pains to 
examine this question, and wou'd invent a system, to 
account for the direct origin of this opinion from the 
imagination, we shou'd be able, by the examination 
of that system, to pronounce a certain judgment in 
the present subject. Let it be taken for granted, that 
our perceptions are broken, and interrupted, and how- 
ever like, are still different from each other; and let 
any one upon this supposition shew why the fancy, 
directly and immediately, proceeds to the belief of 
another existence, resembling these perceptions in their 
nature, but yet continu'd, and uninterrupted, and iden- 



238 A TREATISE OF HUMAN NATURE PART IV 

tical ; and after he has done this to my satisfaction, I 
promise to renounce my present opinion. Mean while 
I cannot forbear concluding, from the very abstracted- 
ness and difficulty of the first supposition, that 'tis 
an improper subject for the fancy to work upon. Who- 
ever wou'd explain the origin of the common opinion 
concerning the continu'd and distinct existence of 
body, must take the mind in its common situation, and 
must proceed upon the supposition, that our percep- 
tions are our only objects, and continue to exist even 
when they are not perceiv'd. Tho' this opinion be 
false, 'tis the most natural of any, and has alone any 
primary recommendation to the fancy. 

As to the second part of the proposition, that the 
philosophical system acquires all its influence on the 
imagination from the vulgar one; we may observe, 
that this is a natural and unavoidable consequence of 
the foregoing conclusion, that it has no primary recom- 
mendation to reason, or the imagination. For as the 
philosophical system is found by experience to take 
hold of many minds, and in particular of all those, who 
reflect ever so little on this subject, it must derive all 
its authority from the vulgar system; since it has no 
original authority of its own. The manner, in which 
these two systems, tho' directly contrary, are con- 
nected together, may be explain'd, as follows. 

The imagination naturally runs on in this train of 
thinking. Our perceptions are our only objects: Re- 
sembling perceptions are the same, however broken or 
uninterrupted in their appearance: This appearing in- 
terruption is contrary to the identity : The interruption 
consequently extends not beyond the appearance, and 
the perception or object really continues to exist, even 
when absent from us: Our sensible perceptions have, 



SECT. II BOOK I. OF THE UNDERSTANDING 239 

therefore, a continu'd and uninterrupted existence. 
But as a little reflection destroys this conclusion, that 
our perceptions have a continu'd existence, by shewing 
that they have a dependent one, 'twou'd naturally be 
expected, that we must altogether reject the opinion, 
that there is such a thing in nature as a continu'd 
existence, which is preserv'd even when it no longer 
appears to the senses. The case, however, is other- 
wise. Philosophers are so far from rejecting the 
opinion of a continu'd existence upon rejecting that of 
the independence and continuance of our sensible 
perceptions, that tho' all sects agree in the latter sen- 
timent, the former, which is, in a manner, its necessary 
consequence, has been peculiar to a few extravagant 
sceptics ; who after all maintain'd that opinion in words 
only, and were never able to bring themselves sin- 
cerely to believe it. 

There is a great difference betwixt such opinions 
as we form after a calm and profound reflection, and 
such as we embrace by a kind of instinct or natural 
impulse, on account of their suitableness and conform- 
ity to the mind. If these opinions become contrary, 
'tis not difficult to foresee which of them will have 
the advantage. As long as our attention is bent upon 
the subject, the philosophical and study 'd principle may 
prevail ; but the moment we relax our thoughts, nature 
will display herself, and draw us back to our former 
opinion. Nay she has sometimes such an influence, 
that she can stop our progress, even in the midst of 
our most profound reflections, and keep us from run- 
ning on with all the consequences of any philosophical 
opinion. Thus tho' we clearly perceive the depend- 
ence and interruption of our perceptions, we stop short 
in our career, and never upon that account reject the 



240 A TREATISE OF HUMAN NATURE PART IV 

notion of an independent and continu'd existence. 
That opinion has taken such deep root in the imagina- 
tion, that 'tis impossible ever to eradicate it, nor will 
any strain'd metaphysical conviction of the dependence 
of our perceptions be sufficient for that purpose. 

But tho' our natural and obvious principles here 
prevail above our study'd reflections, 'tis certain there 
must be some struggle and opposition in the case; at 
least so long as these reflections retain any force or 
vivacity. In order to set ourselves at ease in this par- 
ticular, we contrive a new hypothesis, which seems to 
comprehend both these principles of reason and imag- 
ination. This hypothesis is the philosophical one of 
the double existence of perceptions and objects ; which 
pleases our reason, in allowing, that our dependent 
perceptions are interrupted and different ; and at the 
same time is agreeable to the imagination, in attribut- 
ing a continu'd existence to something else, which we 
call objects. This philosophical system, therefore, is 
the monstrous offspring of two principles, which are 
contrary to each other, which are both at once em- 
brac'd by the mind, and which are unable mutually to 
destroy each other. The imagination tells us, that our 
resembling perceptions have a continu'd and uninter- 
rupted existence, and are not annihilated by their ab- 
sence. Reflection tells us, that even our resembling 
perceptions are interrupted in their existence, and dif- 
ferent from each other. The contradiction betwixt 
these opinions we elude by a new fiction, which is con- 
formable to the hypotheses both of reflection and 
fancy, by ascribing these contrary qualities to different 
existences; the interruption to perceptions, and the 
continuance to objects. Nature is obstinate, and will 
not quit the field, however strongly attack'd by reason ; 



SECT. II BOOK I. OF THE UNDERSTANDING 241 

and at the same time reason is so clear in the point, 
that there is no possibility of disguising her. Not 
being able to reconcile these two enemies, we endeavour 
to set ourselves at ease as much as possible, by succes- 
sively granting to each whatever it demands, and by 
feigning a double existence, where each may find some- 
thing, that has all the conditions it desires. Were we 
fully convinc'd, that our resembling perceptions are 
continu'd, and identical, and independent, we shou'd 
never run into this opinion of a double existence ; since 
we shou'd find satisfaction in our first supposition, and 
wou'd not look beyond. Again, were we fully con- 
vinc'd, that our perceptions are dependent, and inter- 
rupted, and different, we shou'd be as little inclin'd to 
embrace the opinion of a double existence; since in 
that case we shou'd clearly perceive the error of our 
first supposition of a continu'd existence, and wou'd 
never regard it any farther. Tis therefore from the 
intermediate situation of the mind, that this opinion 
arises, and from such an adherence to these two con- 
trary principles, as makes us seek some pretext to 
justify our receiving both; which happily at last is 
found in the system of a double existence. 

Another advantage of this philosophical system is 
its similarity to the vulgar one; by which means we 
can humour our reason for a moment, when it becomes 
troublesome and sollicitous ; and yet upon its least neg- 
ligence or inattention, can easily return to our vulgar 
and natural notions. Accordingly we find, that phil- 
osophers neglect not this advantage; but immediately 
upon leaving their closets, mingle with the rest of man- 
kind in those exploded opinions, that our perceptions 
are our only objects, and continue identically and unin- 



242 A TREATISE OF HUMAN NATURE PART IV 

terruptedly the same in all their interrupted appear- 
ances. 

There are other particulars of this system, wherein 
we may remark its dependence on the fancy, in a very 
conspicuous manner. Of these, I shall observe the two 
following. First, We suppose external objects to re- 
semble internal perceptions. I have already shewn, 
that the relation of cause and effect can never afford 
us any just conclusion from the existence or quali- 
ties of our perceptions to the existence of external con- 
tinu'd objects : And I shall farther add, that even tho' 
they cou'd afford such a conclusion, we shou'd never 
have any reason to infer, that our objects resemble our 
perceptions. That opinion, therefore, is deriv'd from 
nothing but the quality of the fancy above-explain'd, 
that it borrows all its ideas from some precedent per- 
ception. We never can conceive any thing but percep- 
tions, and therefore must make every thing resemble 
them. 

Secondly, As we suppose our objects in general to 
resemble our perceptions, so we take it for granted, 
that every partieular object resembles that perception, 
which it causes. The relation of cause and effect de- 
termines us to join the other of resemblance; and the 
ideas of these existences being already united together 
in the fancy by the former relation, we naturally add 
the latter to compleat the union. We have a strong 
propensity to compleat every union by joining new 
relations to those which we have before observ'd be- 
twixt any ideas, as we shall have occasion to observe 
presently. 1 

Having thus given an account of all the systems 
both popular and philosophical, with regard to exter* 

1 Sect 5 



SECT. II BOOK I. OF THE UNDERSTANDING 243 

nal existences, I cannot forbear giving vent to a certain 
sentiment, which arises upon reviewing those systems. 
I begun this subject with premising, that we ought to 
have an implicit faith in our senses, and that this wou'd 
be the conclusion, I shou'd draw from the whole of 
my reasoning. But to be ingenuous, I feel myself at 
present of a quite contrary sentiment, and am more 
inclin'd to repose no faith at all in my senses, or rather 
imagination, than to place in it such an implicit confi- 
dence. I cannot conceive how such trivial qualities of 
the fancy, conducted by such false suppositions, can 
ever lead to any solid and rational system. They are 
the coherence and constancy of our perceptions, which 
produce the opinion of their continu'd existence; tho' 
these qualities of perceptions have no perceivable con- 
nexion with such an existence. The constancy of our 
perceptions has the most considerable effect, and yet 
is attended with the greatest difficulties. 'Tis a gross 
illusion to suppose, that our resembling perceptions 
are numerically the same; and 'tis this illusion, which 
leads us into the opinion, that these perceptions are 
uninterrupted, and are still existent, even when they 
are not present to the senses. This is the case with 
our popular system. And as to our philosophical one, 
'tis liable to the same difficulties ; and is over-and-above 
loaded with this absurdity, that it at once denies and 
establishes the vulgar supposition. Philosophers deny 
our resembling perceptions to be identically the same, 
and uninterrupted ; and yet have so great a propensity 
to believe them such, that they arbitrarily invent a new 
set of perceptions, to which they attribute these qual- 
ities. I say, a new set of perceptions: For we may 
well suppose in general, but 'tis impossible for us dis- 
tinctly to conceive, objects to be in their nature any 



244 A TREATISE OF HUMAN NATURE PART IV 

thing but exactly the same with perceptions. What 
then can we look for from this confusion of ground- 
less and extraordinary opinions but error and false- 
hood ? And how can we justify to ourselves any belief 
we repose in them? 

This sceptical doubt, both with respect to reason 
and the senses, is a malady, which can never be radi- 
cally cur'd, but must return upon us every moment, 
however we may chace it away, and sometimes may 
seem entirely free from it. 'Tis impossible upon any 
system to defend either our understanding or senses; 
and we but expose them farther when we endeavour 
to justify them in that manner. As the sceptical doubt 
arises naturally from a profound and intense reflection 
on those subjects, it always encreases, the farther we 
carry our reflections, whether in opposition or con- 
formity to it. Carelessness and in-attention alone can 
afford us any remedy. For this reason I rely entirely 
upon them; and take it for granted, whatever may be 
the reader's opinion at this present moment, that an 
hour hence he will be persuaded there is both an 
external and internal world ; and going upon that sup- 
position, I intend to examine some general systems 
both ancient and modern, which have been propos'd 
of both, before I proceed to a more particular enquiry 
concerning our impressions. This will not, perhaps, in 
the end be found foreign to our present purpose. 



Section VI. 
Of personal identity. 

There are some philosophers, who imagine we are 
every moment intimately conscious of what we call our 
Self; that we feel its existence and its continuance 
in existence; and are certain, beyond the evidence of 
demonstration, both of its perfect identity and sim- 
plicity. The strongest sensation, the most violent pas- 
sion, say they, instead of distracting us from this view, 
only fix it the more intensely, and make us consider 
their influence on self either by their pain or pleasure. 
To attempt a farther proof of this were to weaken its 
evidence ; since no proof can be deriv'd from any fact, 
of which we are so intimately conscious; nor is there 
any thing, of which we can be certain, if we doubt 
of this. 

Unluckily all these positive assertions are contrary 
to that very experience, which is pleaded for them, nor 
have we any idea of self, after the manner it is here 
explain'd. For from what impression cou'd this idea 
be deriv'd? This question 'tis impossible to answer 
without a manifest contradiction and absurdity ; and 
yet 'tis a question, which must necessarily be answer'd, 
if we wou'd have the idea of self pass for clear and 
intelligible. It must be some one impression, that gives 
rise to every real idea. (But self or person is not an) 
one impression, but that to which our several impres- 
sions and ideas are suppos'd to have a reference.) If 
any impression gives rise to the idea of self, that im- 



246 A TREATISE OF HUMAN NATURE PART IV 

pression must continue invariably the same, thro' the 
whole course of our lives; since self is suppos'd to 
exist after that manner. But there is no impression 
constant and invariable. Pain and pleasure, grief and 
joy, passions and sensations succeed each other, and 
never all exist at the same time. It cannot, therefore, 
be from any of these impressions, or from any other, 
that the idea of self is deriv'd ; and consequently there 
is no such idea. 

But farther, what must become of all our particu- 
lar perceptions upon this hypothesis? All these are 
different, and distinguishable, and separable from each 
other, and may be separately consider'd, and may exist 
separately, and have no need of any thing to support 
their existence. After what manner, therefore, do 
they belong to self; and how are they connected with 
it? ,For my part, when I enter most intimately into 
what I call myself, I always stumble on some particu- 
lar perception or other, of heat or cold, light or shade, 
love or hatred, pain or pleasure. I never can catch 
myself at any time without a perception, and never 
can observe any thing but the perception. When my 
perceptions are remov'd for any time, as by sound 
sleep ; so long am I insensible of myself, and may truly 
be said not to exist. And were all my perceptions 
remov'd by death, and cou'd I neither think, nor feel, 
nor see, nor love, nor hate after the dissolution of my 
body, I shou'd be entirely annihilated, nor do I con- 
ceive what is farther requisite to make me a perfect 
non-entity. If any one upon serious and unprejudic'd 
reflexion, thinks he has a different notion of himself, 
I must confess I can reason no longer with him. All 
I can allow him is, that he may be in the right as well 
as I, and that we are essentially different in this par- 






SECT. VI BOOK I. OF THE UNDERSTANDING 247 

ticular. He may, perhaps, perceive something simple_ .jji ^ 

and con tinu'd, which he calls himself; tho' I am cer- ^ A/ 

tain there is no such principle in me. m^U^, • jj 

But setting aside some metaphysicians of this kind, / «Xv^>^^ 
I may venture to affirm of the rest of mankind, that 
they are nothing but a bundle or collection of different 
perceptions, which succeed each other with an incon- 
ceivable rapidity, and are in a perpetual flux and move- 
ment. Our eyes cannot turn in their sockets without 
varying our perceptions. Our thought is still more 
variable than our sight; and all our other senses and 
faculties contribute to this change; nor is there any 
single power of the soul, which remains unalterably 
the same, perhaps for one moment. The mind is a 
kind of theatre, where several perceptions successively 
make their appearance; pass, re-pass, glide away, and 
mingle in an infinite variety of postures and situations. 
There is properly no simplicity in it at one time, nor 
identity in different; whatever natural propension we 
may have to imagine that simplicity and identity. 
The comparison of the theatre must not mislead us. 
They are the successive perceptions only, that con- 
stitute the mind; nor have we the most distant notion 
of the place, where these scenes are represented, or of 
the materials, of which it is compos'd. 

What then gives us so great a propension to ascribe & >^* 'jjt^.* 
an identity to these successive perceptions, and to sup- AgP^ (fe 
pose ourselves possest of an invariable and uninter- * 0^ 
rupted existence thro' the whole course of our lives? 
In order to answer this question, we must distinguish 
betwixt personal identity, as it regards our thought or 
imagination, and as it regards our passions or the con- 
cern we take in ourselves. The first is our present 
subject; and to explain it perfectly we must take the 



248 A TREATISE OP HUMAN NATURE PART IV 

matter pretty deep, and account for that identity, which 
we attribute to plants and animals ; there being a great 
analogy betwixt it, and the identity of a self or person. 
We have a distinct idea of an object, that remains 
invariable and uninterrupted thro' a suppos'd varia- 
tion of time; and this idea we call that of identity or 
sameness. We have also a distinct idea of several 
different objects existing in succession, and connected 
together by a close relation; and this to an accurate 
view affords as perfect a notion of diversity, as if there 
was no manner of relation among the objects. But 
tho' these two ideas of identity, and a succession of 
related objects be in themselves perfectly distinct, and 
even contrary, yet 'tis certain, that in our common way 
of thinking they are generally confounded with each 
other. That action of the imagination, by which we 
consider the uninterrupted and invariable object, and 
that by which we reflect on the succession of related 
objects, are almost the same to the feeling, nor is there 
much more effort of thought requir'd in the latter case 
than in the former. The relation facilitates the tran- 
sition of the mind from one object to another, and 
renders its passage as smooth as if it contemplated 
one continu'd object. This resemblance is the cause 
of the confusion and mistake, and makes us substitute 
the notion of identity, instead of that of related objects. 
However at one instant we may consider the related 
succession as variable or interrupted, we are sure the 
next to ascribe to it a perfect identity, and regard it 
as invariable and uninterrupted. Our propensity to 
this mistake is so great from the resemblance above- 
mention'd, that we fall into it before we are aware; 
and tho' we incessantly correct ourselves by reflexion, 
and return to a more accurate method of thinking, 



SECT. VI BOOK I. OF THE UNDERSTANDING 249 

yet we cannot long sustain our philosophy, or take off 
this biass from the imagination. Our last resource 
is to yield to it, and boldly assert that these different 
related objects are in effect the same, however inter- 
rupted and variable. In order to justify to ourselve s 
this absurdity, we often If eign| some new and unintel- 
ligible principle, that connects the objects together, 
and prevents their interruption or variation. Thus 
we-' feign the continu'd existence of the perceptions of 
our senses, to remove the interruption; and run into 
the notion of a soul, and self, and substance, to dis- 
guise the variation. But we may farther observe, that 
where we do not give rise to such a fiction , our pro- 
pension to confound identity with relation is so great, 
that we are apt to imagine 1 something unknown and 
mysterious, connecting the parts, beside their relation ; 
and this I take to be the case with regard to the iden- 
tity we ascribe to plants and vegetables. And even 
when this does not take place, we still feel a propen- 
sity to confound these ideas, tho' we are not able fully 
to satisfy ourselves in that particular, nor find any 
thing invariable and uninterrupted to justify our no- 
tion of identity. 

Thus the controversy concerning identity is not 
merely a dispute of words. For when we attribute 
identity, in an improper sense, to variable or inter- 
rupted objects, our mistake is not confin'd to the ex- 
pression, but is commonly attended with a fiction, 
either of something invariable and uninterrupted, or 

1 If the reader is desirous to see how a great genius may be 
influenc'd by these seemingly trivial principles of the imagination, 
as well as the mere vulgar, let him read my Lord Shaftsbury's 
reasonings concerning the uniting principle of the universe, and 
the identity of plants and animals. See his Moralists: or, Philo- 
sophical rhapsody. 



250 A TREATISE OF HUMAN NATURE PART IV 

of something mysterious and inexplicable, or at least 
with a propensity to such fictions. What will suffice 
to prove this hypothesis to the satisfaction of every 
fair enquirer, is to shew from daily experience and 
observation, that the objects, which are variable or 
interrupted, and yet are suppos'd to continue the 
same, are such only as consist of a succession of parts, 
connected together by resemblance, contiguity, or 
causation. For as such a succession answers evidently 
to our notion of diversity, it can only be by mistake 
we ascribe to it an identity; and as the relation of 
parts, which leads us into this mistake, is really noth- 
ing but a quality, which produces an association of 
ideas, and an easy transition of the imagination from 
one to another, it can only be from the resemblance, 
which this act of the mind bears to that, by which we 
contemplate one continu'd object, that the error arises. 
Our chief business, then, must be to prove, that all 
objects, to which we ascribe identity, without observ- 
ing their invariableness and uninterruptedness, are 
such as consist of a succession of related objects. 

In order to this, suppose any mass of matter, of 
which the parts are contiguous and connected, to be 
plac'd before us ; 'tis plain we must attribute a perfect 
identity to this mass, provided all the parts continue 
uninterruptedly and invariably the same, whatever mo- 
tion or change of place we may observe either in the 
whole or in any of the parts. But supposing some 
very small or inconsiderable part to be added to the 
mass, or substracted from it; tho' this absolutely 
destroys the identity of the whole, strictly speaking; 
yet as we seldom think so accurately, we scruple not 
to pronounce a mass of matter the same, where we find 
so trivial an alteration. The passage of the thought 



SECT. VI BOOK I. OF THE UNDERSTANDING 251 

from the object before the change to the object after 
it, is so smooth and easy, that we scarce perceive the 
transition, and are apt to imagine, that 'tis nothing 
but a continu'd survey of the same object. 

There is a very remarkable circumstance, that at- 
tends this experiment; which is, that tho' the change 
of any considerable part in a mass of matter destroys 
the identity of the whole, yet we must measure the 
greatness of the part, not absolutely, but by its pro- 
portion to the whole. The addition or diminution of 
a mountain wou'd not be sufficient to produce a di- 
versity in a planet ; tho' the change of a very few inches 
wou'd be able to destroy the identity of some bodies. 
'Twill be impossible to account for this, but by reflect- 
ing that objects operate upon the mind, and break or 
interrupt the continuity of its actions not according 
to their real greatness, but according to their pro- 
portion to each other: And therefore, since this inter- 
ruption makes an object cease to appear the same, it 
must be the uninterrupted progress of the thought, 
which constitutes the imperfect identity. 

This may be confirm'd by another phenomenon. 
A change in any considerable part of a body destroys 
its identity ; but 'tis remarkable, that where the change 
is produc'd gradually and insensibly we are less apt 
to ascribe to it the same effect. The reason can plainly 
be no other, than that the mind, in following the suc- 
cessive changes of the body, feels an easy passage 
from the surveying its condition in one moment to the 
viewing of it in another, and at no particular time 
perceives any interruption in its actions. From which 
continu'd perception, it ascribes a continu'd existence 
and identity to the object. 



252 A TREATISE OF HUMAN NATURE PART IV 

But whatever precaution we may use in introduc- 
ing the changes gradually, and making them propor- 
tionable to the whole, 'tis certain, that where the 
changes are at last observ'd to become considerable, 
we make a scruple of ascribing identity to such differ- 
ent objects. There is, however, another artifice, by 
which we may induce the imagination to advance a 
step farther; and that is, by producing a reference of 
the parts to each other, and a combination to some 
common end or purpose. A ship, of which a consider- 
able part has been chang'd by frequent reparations, 
is still consider'd as the same; nor does the difference 
of the materials hinder us from ascribing an identity 
to it. The common end, in which the parts conspire, 
is the same under all their variations, and affords an 
easy transition of the imagination from one situation 
of the body to another. 

But this is still more remarkable, when we add a 
sympathy of parts to their common end, and suppose 
that they bear to each other, the reciprocal relation 
of cause and effect in all their actions and operations. 
This is the case with all animals and vegetables ; where 
not only the several parts have a reference to some 
general purpose, but also a mutual dependence on, and 
connexion with each other. The effect of so strong 
a relation is, that tho' every one must allow, that in a 
very few years both vegetables and animals endure a 
total change, yet we still attribute identity to them, 
while their form, size, and substance are entirely al- 
ter'd. An oak, that grows from a small plant to a 
large tree, is still the same oak; tho' there be not one 
particle of matter, or figure of its parts the same. An 
infant becomes a man, and is sometimes fat, sometimes 
lean, without any change in his identity. 



SECT. VI BOOK I. OF THE UNDERSTANDING 253 

We may also consider the two following phe- 
nomena, which are remarkable in their kind. The first 
is, that tho' we commonly be able to distinguish pretty 
exactly betwixt numerical and specific identity, yet it 
sometimes happens, that we confound them, and in our 
thinking and reasoning employ the one for the other. 
Thus a man, who hears a noise, that is frequently 
interrupted and renew'd, says, it is still the same noise ; 
tho' 'tis evident the sounds have only a specific iden- 
tity or resemblance, and there is nothing numerically 
the same, but the cause, which produc'd them. In 
like manner it may be said without breach of the pro- 
priety of language, that such a church, which was 
formerly of brick, fell to ruin, and that the parish 
rebuilt the same church of free-stone, and according 
to modern architecture. Here neither the form nor 
materials are the same, nor is there any thing common 
to the two objects, but their relation to the inhabitants 
of the parish; and yet this alone is sufficient to make 
us denominate them the same. But we must observe, 
that in these cases the first object is in a manner anni- 
hilated before the second comes into existence; by 
which means, we are never presented in any one point 
of time with the idea of difference and multiplicity; 
and for that reason are less scrupulous in calling them 
the same. 

Secondly, We may remark, that tho' in a succes- 
sion* of related objects, it be in a manner requisite, 
that the change of parts be not sudden nor entire, in 
order to preserve the identity, yet where the objects 
are in their nature changeable and inconstant, we 
admit of a more sudden transition, than wou'd other- 
wise be consistent with that relation. Thus as the 
nature of a river consists in the motion and change of 



254 A TREATISE OF HUMAN NATURE PART IV 

parts; tho' in less than four and twenty hours these 
be totally alter'd ; this hinders not the river from con- 
tinuing the same during several ages. What is natu- 
ral and essential to any thing is, in a manner, ex- 
pected ; and what is expected makes less impression, 
and appears of less moment, than what is unusual and 
extraordinary. A considerable change of the former 
kind seems really less to the imagination, than the 
most trivial alteration of the latter; and by breaking 
less the continuity of the thought, has less influence 
in destroying the identity. 

We now proceed to explain the nature of personal 
identity, which has become so great a question in 
philosophy, especially of late years in England, where 
all the abstruser sciences are study'd with a peculiar 
ardour and application. And here 'tis evident, the 
same method of reasoning must be continu'd, which 
has so successfully explain'd the identity of plants, 
and animals, and ships, and houses, and of all the com- 
pounded and changeable productions either of art or 
nature. The identity, which we ascribe to the mind 
of man, is only a fictitious one, and of a like kind 
with that which we ascribe to vegetables and animal 
bodies. It cannot, therefore, have a different origin, 
but must proceed from a like operation of the imag- 
ination upon like objects. 

But lest this argument shou'd not convince the 
reader; tho' in my opinion perfectly decisive; let him 
weigh the following reasoning, which is still closer 
and more immediate. Tis evident, that the identity, 
which we attribute to the human mind, however per- 
fect we may imagine it to be, is not able to run the 
several different perceptions into one, and make them 
lose their characters of distinction and difference, 



SECT. VI BOOK I. OF THE UNDERSTANDING 255 

which are essential to them. Tis still true, that every 
distinct perception, which enters into the composition 
of the mind, is a distinct existence, and is different, 
and distinguishable, and separable from every other 
perception, either contemporary or successive. But, 
as, notwithstanding this distinction and separability, 
we suppose the whole train of perceptions to be united 
by identity, a question naturally arises concerning this 
relation of identity ; whether it be something that really 
binds pur several perceptions together, or only associates 
their ideas in the imagination. That is, in other words, 
whether in pronouncing concerning the identity of a 
person, we observe some real bond among his percep- 
tions, or only feel one among the ideas we form of 
them. This question we might easily decide, if we 
wou'd recollect what has been already prov'd at large, 
that the understanding never observes any real con- 
nexion among objects, and that even the union of 
cause and effect, when strictly examin'd, resolves itself 
into a customary association of ideas. For from thence 
it evidently follows, that identity is nothing really be- 
longing to these different perceptions, and uniting 
them together ; but is merely a quality, which we attri- 
bute to them, because of the union of their ideas in the 
imagination, when we reflect upon them. Now the 
only qualities, which can give ideas an union in the 
imagination, are these three relations above-mention'd. 
These are the uniting principles in the ideal world, 
and without them every distinct object is separable 
by the mind, and may be separately consider'd, and 
appears not to have any more connexion with any 
other object, than if disjoined by the greatest differ- 
ence and remoteness. 'Tis therefore, on some of these 
three relations of resemblance, contiguity and caus- 



256 A TREATISE OF HUMAN NATURE PART IV 

ation, that identity depends; and as the very essence 
of these relations consists in their producing an easy 
transition of ideas ; it follows, that our notions of per- 
sonal identity, proceed entirely from the smooth and 
uninterrupted progress of the thought along a train of 
connected ideas, according to the principles above- 
explain'd. 

The only question, therefore, which remains, is, by 
what relations this uninterrupted progress of our 
thought is produc'd, when we consider the successive 
existence of a mind or thinking person. And here' tis 
evident we must confine ourselves to resemblance and 
causation, and must drop contiguity, which has little 
or no influence in the present case. 

To begin with resemblance ; suppose we cou'd see 
clearly into the breast of another, and observe that 
succession of perceptions, which constitutes his mind 
or thinking principle, and suppose that he always pre- 
serves the memory of a considerable part of past per- 
ceptions; 'tis evident that nothing cou'd more con- 
tribute to the bestowing a relation on this succession 
amidst all its variations. For what is the memory but 
a faculty, by which we raise up the images of past 
perceptions? And as an image necessarily resembles 
its object, must not the frequent placing of these 
lesembling perceptions in the chain of thought, con- 
vey the imagination more easily from one link to 
another, and make the whole seem like the continu- 
ance of one object? In this particular, then, the mem- 
ory not only discovers the identity, but also contributes 
to its production, by producing the relation of resem- 
blance among the perceptions. The case is the same 
whether we consider ourselves or others. 



SECT. VI BOOK I. OF THE UNDERSTANDING 257 

As to causation; we may observe, that the true 
idea of the human mind, is to consider it as a system 
of different perceptions or different existences, which 
are link'd together by the relation of cause and effect, 
and mutually produce, destroy, influence, and modify 
each other. Our impressions give rise to their cor- 
respondent ideas ; and these ideas in their turn pro- 
duce other impressions. One thought chaces another, 
and draws after it a third, by which it is expell'd in 
its turn. In this respect, I cannot compare the soul 
more properly to any thing than to a republic or com- 
monwealth, in which the several members are united 
by the reciprocal ties of government and subordina- 
tion, and give rise to other persons, who propagate 
the same republic in the incessant changes of its parts. 
And as the same individual republic may not only 
change its members, but also its laws and constitu- 
tions; in like manner the same person may vary his 
character and disposition, as well as his impressions 
and ideas, without losing his identity. Whatever 
changes he endures, his several parts are still con- 
nected by the relation of causation. And in this view 
our identity with regard to the passions serves to cor- 
roborate that with regard to the imagination, by the 
making our distant perceptions influence each other, 
and by giving us a present concern for our past or 
future pains or pleasures. 

As memory alone acquaints us with the continu- 
ance and extent of this succession of perceptions, 'tis 
to be consider'd, upon that account chiefly, as the 
source of personal identity. Had we no memory, we 
never shou'd have any notion of causation, nor con- 
sequently of that chain of causes and effects, which 
constitute our self or person. But having once acquir'd 



258 A TREATISE OF HUMAN NATURE PART IV 

this notion of causation from the memory, we can 
extend the same chain of causes, and consequently the 
identity of our persons beyond our memory, and can 
comprehend times, and circumstances, and actions, 
which we have entirely forgot, but suppose in general 
to have existed. For how few of our past actions 
are there, of which we have any memory? Who can 
tell me, for instance, what were his thoughts and 
actions on the first of January 171 5, the nth of March 
1719, and the 3d of August 1733? Or will he affirm 
because he has entirely forgot the incidents of these 
days, that the present self is not the same person with 
the self of that time ; and by that means overturn all 
the most established notions of personal identity? In 
this view, therefore, memory does not so much produce 
as discover personal identity, by shewing us the rela- 
tion of cause and effect among our different percep- 
tions. 'Twill be incumbent on those, who affirm that 
memory produces entirely our personal identity, to 
give a reason why we can thus extend our identity 
beyond our memory. 

The whole of this doctrine leads us to a conclu- 
sion, which is of great importance in the present affair, 
viz. that all the nice and subtile questions concerning 
personal identity can never possibly be decided, and 
are to be regarded rather as grammatical than as phil- 
osophical difficulties. Identity depends on the rela- 
tion of ideas; and these relations produce identity, by 
means of that easy transition they occasion. But as 
the relations, and the easiness of the transition may 
diminish by insensible degrees, we have no just stand- 
ard, by which we can decide any dispute concerning 
the time, when they acquire or lose a title to the name 
of identity. All the disputes concerning the identity 



SECT. VI BOOK I. OF THE UNDERSTANDING 259 

of connected objects are merely verbal, except so far 
as the relation of parts gives rise to some fiction or 
imaginary principle of union, as we have already 
observ'd. 

What I have said concerning the first origin and 
uncertainty of our notion of identity, as apply'd to the 
human mind, may be extended with little or no varia- 
tion to that of simplicity. An object, whose different 
co-existent parts are bound together by a close rela- 
tion, operates upon the imagination after much the 
same manner as one perfectly simple and indivisible, 
and requires not a much greater stretch of thought in 
order to its conception. From this similarity of opera- 
tion we attribute a simplicity to it, and feign a prin- 
ciple of union as the support of this simplicity, and 
the center of all the different parts and qualities of 
the object. 

Thus we have finish'd our examination of the sev- 
eral systems of philosophy, both of the intellectual and 
moral world ; and in our miscellaneous way of reason- 
ing have been led into several topics ; which will either 
illustrate and confirm some preceding part of this dis- 
course, or prepare the way for our following opinions. 
'Tis now time to return to a more close examination 
of our subject, and to proceed in the accurate anatomy 
of human nature, having fully explain'd the nature 
of our judgment and understanding. 

$ # $ ^s" $ # 



APPENDIX. 
****** 

I had entertain'd some hopes, that however de- 
ficient our theory of the intellectual world might be, 
it wou'd be free from those contradictions, and absurd- 
ities, which seem to attend every explication, that hu- 
man reason can give of the material world. But upon 
a more strict review of the section concerning personal 
identity, I find myself involv'd in such a labyrinth, 
that, I. must confess, I neither know how to correct 
my former opinions, nor how to render them consis- 
tent. If this be not a good general reason for scep- 
ticism, 'tis at least a sufficient one (if I were not 
already abundantly supplied) for me to entertain a 
diffidence and modesty in all my decisions. I shall 
propose the arguments on both sides, beginning with 
those that induc'd me to deny the strict and proper 
identity and simplicity of a self or thinking being. 

When we talk of self or substance, we must have 
an idea annex'd to these terms, otherwise they are 
altogether unintelligible. Every idea is deriv'd from 
preceding impressions ; and we have no impression of 
self or substance, as something simple and individual. 
We have, therefore, no idea of them in that sense. 

Whatever is distinct, is distinguishable; and what- 
ever is distinguishable, is separable by the thought or 
imagination. All perceptions are distinct. They are, 
therefore, distinguishable, and separable, and may be 
conceiv'd as separately existent, and may exist sepa- 
rately, without any contradiction or absurdity. 



APPENDIX 261 

When I view this table and that chimney, nothing 
is present to me but particular perceptions, which are 
of a like nature with all the other perceptions. This is 
the doctrine of philosophers. But this table, which is 
present to me, and that chimney, may and do exist 
separately. This is the doctrine of the vulgar, and 
implies no contradiction. There is no contradiction, 
therefore, in extending the same doctrine to all the 
perceptions. 

In general, the following reasoning seems satis- 
factory. All ideas are borrow'd from preceding per- 
ceptions. Our ideas of objects, therefore, are deriv'd 
from that source. Consequently no proposition can 
be intelligible or consistent with regard to objects, 
which is not so with regard to perceptions. But 'tis 
intelligible and consistent to say, that objects exist 
distinct and independent, without any common simple 
substance or subject of inhesion. This proposition, 
therefore, can never be absurd with regard to percep- 
tions. 

When I turn my reflexion on myself, I never can 
perceive this self without some one or more percep- 
tions ; nor can I ever perceive any thing but the percep- 
tions. 'Tis the composition of these, therefore, which 
forms the self. 

We can conceive a thinking being to have either 
many or few perceptions. Suppose the mind to be 
reduc'd even below the life of an oyster. Suppose it 
to have only one perception, as of thirst or hunger. 
Consider it in that situation. Do you conceive any 
thing but merely that perception? Have you any no- 
tion of self or substance? If not, the addition of other 
perceptions can never give you that notion. 



262 A TREATISE OF HUMAN NATURE 

The annihilation, which some people suppose to 
follow upon death, and which entirely destroys this 
self, is nothing but an extinction of all particular per- 
ceptions; love and hatred, pain and pleasure, thought 
and sensation. These therefore must be the same with 
self; since the one cannot survive the other. 

Is self the same with substance ? If it be, how can 
that question have place, concerning the subsistence of 
self, under a change of substance? If they be distinct, 
what is the difference betwixt them? For my part, 
I have a notion of neither, when conceiv'd distinct 
from particular perceptions. 

Philosophers begin to be reconcil'd to the principle, 
that we have no idea of external substance, distinct 
from the ideas of particular qualities. This must pave 
the. way for a like principle with regard to the mind, 
that we have no notion of it, distinct from the par- 
ticular perceptions. 

So far I seem to be attended with sufficient evi- 
dence. But having thus loosen'd all our particular 
perceptions, when 1 I proceed to explain the principle 
of connexion, which binds them together, and makes 
us attribute to them a real simplicity and identity; I 
am sensible, that my account is very defective, and 
that nothing but the seeming evidence of the precedent 
reasonings cou'd have induc'd me to receive it. (If 
perceptions are distinct existences, they form a whole 
only by being connected together. But no connexions 
among distinct existences are ever discoverable by 
human understanding. J We only feel _a connexion or 
determination of the thought, to pass from one object 
to another. It follows, therefore, that the thought 
alone finds personal identity, when reflecting on the 
train of past perceptions, that compose a mind, the 



APPENDIX 263 

ideas of them are felt to be connected together, and 
naturally introduce each other. However extraordin- 
ary this conclusion may seem, it need not surprize us. 
Most philosophers seem inclin'd to think, that per- 
sonal identity arises from consciousness; and con- 
sciousness is nothing but a reflected thought or per- 
ception. The present philosophy, therefore, has so far 
a promising aspect. But all my hopes vanish, when I 
come to explain the principles, that unite our success- 
ive perceptions in our thought or consciousness. I 
cannot discover any theory, which gives me satisfac- 
tion on this head. 

In short there are two principles, which I cannot 
render consistent; nor is it in my power to renounce 
either of them, viz. that all our distinct perceptions are - 

distinct existences, and that the mind never perceives '^^\Z^ 
any real connexion among distinct existences. /Ola 
Pflmr perceptions either inhere in something simple and 
' I individual, or did the mind perceive some real connex- 
ion among them, there wou'd be no difficulty in the 
case. For my part, I must plead the privilege of a 
sceptic, and confess, that this difficulty is too hard for 
my understanding. I pretend not, however, to pro- 
nounce it absolutely insuperable. Others, perhaps, or 
myself, upon more mature reflexions, may discover 
some hypothesis, that will reconcile those contradic- 
tions. 



r . <5$~* ,'v~ -1U W«vU « « < &ju^u^ , 



INDEX 



Abstraction, 164. 

Abstract sciences, 167, 173. 

Academic philosophy, 41 et seq. 

Accuracy, 6. 

Addison, 3. 

Alchemy, 136. 

Alexander, 87. 

Alexander, the false prophet, 126. 

Algebra, 187. 

Ambiguous expressions, 83. 

Analogy, reasoning by, 109. 

Animals, reason of, 109 et seq. 

Annihilation, 22. 

A priori, 25, 26, 34, 44. 

Aqua regia, 22S. 

Arguments, demonstrative, 57; 
probable, 57; mutual destruc- 
tion Of, 121. 

Arithmetic, 187. 

Aristotle, 3, 86. 

Association of ideas, 21 et seq., 
51 et seq., 255. 

Assurance, degrees of, 115. 

Astronomy, 175. 

Atheists, 159. 

Athens, 139, 141. 

Aurelius, Marcus, 126. 

Bacon, 136. 

Bayle, 164. 

Bede, 132. 

Belief, 47 et seq., 50 et seq., 60, 

112, 196. 
Berkeley, 164. 
Bible, 137. 

Billiard-ball, 27, 48, 64, 72, 78, 81. 
Bodies, operation of, 76, 84 et 

seq., 95- 
Body, existence of, 232 et seq. 

Caesar, 174. 
Cartesians, 207 et seq. 



Cartesian doubt, 159. 

Catastrophes, 135. 

Cato, 119. 

Causation, 77 et seq., 185 et seq., 
257. 

Cause and effect, 22 et seq., 42 et 
seq,. 84 et seq., 143 et seq., 
169, 198, et seq., 255. 

Causes, ultimate, 29 et seq.; simi- 
lar, 35 et seq.; final, 56; prob- 
ability of, 58; invisible, 71; oc- 
casional, 72; definition, 219. 

Chance, 57 et seq., 99, 221. 

Chemistry, 175. 

Child, burnt, 38. 

Christian religion, 114, 137, 138. 

Chronology, 175. 

Cicero, 3, 53, 124. 

Clarke, 76, 199. 

Climates, 59. 

Color-sensation, 18. 

Conduct, human, determinism and 
liberty in, 85 et seq. 

Conjecture, 154. 

Conjunction, 72 et seq., 76 et seq., 
85, 169; customary, 47, 50; con- 
stant, 96, 231. 

Connexion, 25 et seq., 32, 36, 51 
et seq., 72 et seq.; necessary, 
61 et seq., 64, 76 et seq., 99, 
196, 202 et seq. 

Constraint, 100. 

Contiguity, 22 et seq., 53 et seq., 
192, et seq. 

Continued existence of objects, 
232 et seq. 

Contrariety, 22, 185. 

Contrast, 22. 

Copies of impressions, ideas, 16 
et seq., 63 et seq., 80, 189, 208, 

211, 222, 227. 



INDEX 



265 



Creator, responsibility of, 104. 
Criticism, 175. 
Cudworth, 76. 
Curtius, Quintus, 87. 
Custom, 43 et seq., 55, 112. 
Customary, connexion, 80 et seq.; 
transition, 79 et seq., 95. 

Definitions, exact, 82. 

Deity, 207 et seq. 

Demetrius, 129. 

Demonstration, proper objects of, 

173. 
Demonstrative, arguments, 57; 

reasoning, 34. 
Demosthenes, 124. 
Descartes, 76, 158. 
Design, 151. 
Determination of the mind, 203, 

213 et seq. 
Determinism, 83 et seq. 
Distance, 235. 
Distinctness, 231 et seq., 260 et 

seq. 
Divine existence, argument for, 

143- 
Divinity, 175. 
Divisibility, infinite, 166. 
Doubt, Cartesian, 159. 
Dreams, 162. 
Dye, 57- 

Effect. See Cause. 

Elizabeth, Queen, 135. 

Eloquence, 124. 

End, common, 252. 

Endeavour, 69. 

Energy, 63, 80; of causes, 205 
See Force. 

Epicurus, 139 et seq., 141 et seq., 
i55> 170. 

Ethics, 148 et seq. 

Euclid, 23, 62. 

Evidence, 24; natural, 93 et seq.; 
for the truth of Christian re- 
ligion, 114; contrariety of, 118; 
of sense, 160 et seq.; objections 
to moral, 168 et seq. 

Evil, 105 et seq. 

Existence, idea of, 229 et seq.; 
continued, of objects, 232 et 



seq.; distinct, of objects, 233 et 
seq. 

Experience, 26 et seq., 134, 162, 
174; foundation of conclusions 
from, 31 et seq.; reasonings 
from, 35, 41; inferences from, 
44; the foundation of evidence, 
115 et seq., 186 et seq., 201. 

Experiments, 116, 235. 

Extension, idea of, 164. 

External objects, belief of, 161 et 
seq. 

Extraordinary, the, 118 et seq. 

Fact, matters of, 23 et seq. 

Faith, 137, 138. 

Fiction, 48. 

Final causes, 56. 

Force, 63, 80, 204 et seq., 209 

et seq., 231. 
Free will, 83 et seq. 
Future state, 139 et seq. 

Gabriel, 174. 

General ideas, 164, 168, 209. 
Geography, 175; mental, 10. 
Geometry, 29, 61, 168, 187. 
God, 73, 74, 104, 107, 136, 153, 

156, 163. 
Gods, the, 144 et seq. 
Gravity, 59. 

Habit, 43 et seq. 

Harmony, pre-established, 55. 

Heredotus, 132. 

Hippocrates, 86. 

History, 93, 175. 

Hobbes, 198. 

Human body, 90. 

Human nature, science of, 1 et 

seq.; principles and operations 

of, 85 et seq. 
Human mind, 254. 
Hypothesis, 149. 

Ideas, origin of, 14 et seq.; asso- 
ciation of, 21 et seq.; relations 
of, 23 et seq.; complex, 63; 
copies of our impressions, 63 et 
seq., 80, 189, 208, 211, 222, 227, 
general, 164, 168. 



266 



INDEX 



Identity, 185, 190. 
Identity, personal, 245 et seq. 
Identity, of objects, 250 et seq. 
Images, sensible, 52. 
Imagination, 47 et seq., 49, 172, 

234 et seq. 
Impostures, 126. 
Impressions, 15 et seq.; original, 

63; of power, 213. 
Indeterminism, 83 et seq. 
Indian prince, 119. 
Infinite divisibility, 166. 
Innate, 19; ideas, 208. 
Instincts, 113. 
Invisible causes, 71. 

Jansenist miracles, 131. 
Jesuits, 131. 
Jupiter, 145, 146. 
Justice, distributive, 149. 

La Bruyere, 3. 

Liberty, 83 et seq.; denned, 99. 

Limbs, use of our, 56. 

Livy, 128, 136. 

Locke, 4, 20, 57, 65, 76, 200, 204. 

Lucian, 126, 139, 140. 

Lucretius, 132. 

Magic, 136. 

Mahomet, 128. 

Malebranche, 3, 76, 205. 

Mankind, the same in all times 
and places, 86 et seq. 

Mariana, 132. 

Marvellous, the, 118 et seq.; pro- 
pensity to the, 124 et seq. 

Mathematics, 23, 30, 61, 174, 187. 

Matters of fact, 23 et seq., 176. 

Medicine, 90. 

Mental, geography, 10; research, 
11. 

Metaphysics, 5 et seq., 62, 176. 

Mind, command of, over the body, 
70. 

Miracles, 114 et seq.; denned, 
121; reasons for discrediting, 
122 et seq. 

Mode, 227 et seq. 

Moral evidence, ^3 et seq.; objec- 
tions to, 168 et seq. 



Morality, doctrines of necessity 
and of liberty consistent with, 
100. 

Moral, philosophy, 1 et seq.; rea- 
soning, 34, 175. 

Morals, 93, 175. 

Motion, 27. 

Motives and voluntary actions, 
conjunction between, 85 et seq. 

Muscovy, 119. 

Myself. See Self. 

Natural evidence, 93 et seq. 

Natural philosophy, 175. 

Nature, course of, 150; violations 

of the course of, 134. 
Necessary connexion, 64, 196, 2^2 

et seq. 
Necessity, 83 et seq., 98 et sec^ ; 

as an inference, 85; defined, 

100, 197 et seq., 216; in U.e 

mind, 214. 
Newton, 75. 
Number, 173, 176, 185 et seq. 

Occasions, 72 et seq. 
Objects, sensible, 52, 232 et seq ; 
external, 242. 

Paphlagonia, 126. 
Paris, Abbe, 131. 
Pentateuch, 137. 
Perceptions, 14. 
Pharsalia, battle of, 131. 
Philippi, battle of, 131. 
Philosophers, fame of, 3. 
Philosophy, 139 et seq.; nature of, 

1 et seq.; natural, 175. 
Physic, 175. 
Plutarch, 128, 132. 
Points, mathematical, 166. 
Politics, 93. 
Polybius, 86. 
Possibility, 149. 
Power, 63, 64, 68 et seq., 80, 204 

et seq.; impression of, 213. See 

Force. 
Pre-established harmony, 55. 
Pre-ordination, 103. 
Priority, 193. 



tNDBX 



267 



Probability, 57 et seq., 116 et seq., 
120, 134- 

Prodigies, reasons for discredit- 
ing, 122 et seq. 

Proofs, 57, 116 et seq., 120, 134. 

Prophecies, 138. 

Prophet, Alexander the false, 126. 

Protagoras, 139. 

Providence, a particular, 139 et 
seq.; divine, 148. 

Public good, questions of, 142. 

Punishments, 101. 

Purpose, 252. 

Pyrrhonism, 168, 170, 172. 

Qualities, sensible, 65; secondary 

and primary, 164. 
Quantity, 173, 176; science of, 

168. 

Reason, 26 et seq.; of animals, 
109 et seq.; attempt to destroy, 
165, 234 et seq. 

Reasoning, two kinds of, 34; con- 
cerning matter of fact, nature 
of, 31 et seq.; a priori, 34; 
demonstrative, 34; moral, 34, 
62, 175; from experience, 41; 
comparison, 190. 

Regular succession, 56. 

Relations of ideas, 23 et seq. 

Relations, philosophical, 185, 219. 

Religion, 123, 127. 

Religious doctrines and life, 155. 

Resemblance, 22 et seq.; 51 et 
seq., 185, 256. 

Retz, Cardinal de, 130. 

Rewards, 101. 

Roman Catholic religion, 52. 

Roman emperors, 140. 

Saragossa, miracle of, 130. 
Sceptical philosophy, 41 et seq., 

158 et seq., 244. 
Scepticism, mitigated, 171; with 

regard to senses, 232 et seq. 
Science, proper subjects of, 173. 
Sciences, abstract, 167, 173. 
Self, idea of, 245 et seq., 260 et 

seq. 



Senses, 32; evidence of, 160 et 
seq.; perceptions of the, 162 et 
seq. 

Sensible, images, 52; objects, 52; 
qualities, 65. 

Serapis, 129. 

Shaftsbury, Lord, 349. 

Similar, causes, 35 et seq.; effects, 
35 et seq.; instances, 81; ob- 
jects, 61, 79. 

Simplicity of mind, 247. 

Socrates, 139. 

Soul, 249. 

Soul with body, union of, 66 et 
seq. 

Space, ideas of, 165 et seq. 

Stoics, 40, 105, 170. 

Substance, 227, 249, 260. 

Succession, regular, 56. 

Suetonius, 129. 

Sumatra, 119. 

Supreme Being, 208. 

Surprise, 123 et seq. 

Tacitus, 86, 128. 

Terms, meaning of, 82. 

Testimony, human, 116 et seq.; 
circumstances requisite to give 
full assurance to, 122. 

Theology, 175. 

Thoughts, 15 et seq. 

Tillotson, Dr., 114. 

Time, ideas of, 165 et seq.; re- 
lations of, 185. 

Transition of the mind, 220. 

Truth, criteria of, 160. 

Ultimate causes, 29 et seq. 
Uniformity in nature, 84 et seq., 
87 et seq. 

Velleity, 98. 

Vespasian, 128. 

Vis inertiae, 75. 

Volition, 66 et seq., 83 et seq. 

Will, 66 et seq., 83 et seq. 
Witnesses, 118. 
Wonder, 123 et seq. 

Zeuxis, 144. 



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